Hey guys, what you are about to listen to is an extremely graphic episode that will contain many scenes of gore, rape, human experimentation, honestly it will run the gambit. If you got a weak stomach, this episode might not be for you. You have been warned. I just want to take a chance to say a big thanks to all of you guys who decided to join the patreon, you guys are awesome! Please leave a comment on this episode to let me know what more you want to hear about in the future. With all of that ...
Hey guys, what you are about to listen to is an extremely graphic episode that will contain many scenes of gore, rape, human experimentation, honestly it will run the gambit. If you got a weak stomach, this episode might not be for you. You have been warned. I just want to take a chance to say a big thanks to all of you guys who decided to join the patreon, you guys are awesome! Please leave a comment on this episode to let me know what more you want to hear about in the future. With all of that said and done lets jump right into it.
Where to begin with this one? Let start off with one of the major figures of Unit 731, Shiro Ishii. Born June 25th, 1892 in the village of Chiyoda Mura in Kamo District of Chiba Prefecture, Ishii was the product of his era. He came from a landowning class, had a very privileged childhood. His primary and secondary schoolmates described him to be brash, abrasive and arrogant. He was a teacher's pet, extremely intelligent, known to have excellent memory. He grew up during Japans ultra militarism/nationalism age, thus like any of his schoolmates was drawn towards the military. Less than a month after graduating from the Medical department of Kyoto Imperial University at the age of 28, he began military training as a probation officer in the 3rd regiment of the Imperial Guards division. Within 6 months he became a surgeon 1st Lt. During his postgraduate studies at Kyoto Imperial university he networked successfully to climb the career ladder. As a researcher he was sent out to help cure an epidemic that broke out in Japan. It was then he invented a water filter that could be carried alongside the troops.
He eventually came across a report of the Geneva Protocol and conference reports of Harada Toyoji as well as other military doctors. He became impressed with the potential of chemical and biological warfare. During WW1 chemical warfare had been highly explored, leading 44 nations to pass the Geneva Protocol or more specifically “Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or other Gases, and of Bacteriological Methods of Warfare”. Representatives from Japan were present at this conference and were involving in the drafting and signing of the Geneva Protocol, but it was not ratified in Japan at the time. Ishii’s university mentor, Kiyano Kenji suggested he travel western countries and he did so for 2 years. Many nations were secretive about their research, but some places such as MIT were quite open. After his visit Ishii came to believe Japan was far behind everyone else in biological warfare research. After returning to Japan Ishii became an instructor at the Imperial Japanese Army Medical School. Japan of course lacked significant natural resources, thus it was a perfect nation to pursue biological weapons research. Ishii began lobbying the IJA, proposing to establish a military agency to develop biological weapons. One of his most compelling arguments was “that biological warfare must possess distinct possibilities, otherwise, it would not have been outlawed by the League of Nations.”
Ishii networked his way into good favor with the Minister of Health, Koizumi Chikahiko who lended his support in August of 1932 to allow Ishii to head an Epidemic Prevention Laboratory. Ishii secured a 1795 square meter complex at the Army Medical College. Yet this did not satisfy Ishii, it simply was not the type of work he wanted to do. The location of Tokyo allowed too many eyes on his work, he could not perform human experimentation. For what he wanted to do, he had to leave Japan, and in the 1930’s Japan had a few colonies or sphere’s of influence, the most appetizing one being Manchuria. In 1932 alongside his childhood friend Masuda Tomosada, Ishii took a tour of Harbin and he fell in love with the location.
During the 1930’s Harbin was quite a cosmopolitan city, it was a major trading port and diverse in ethnicities and religions. Here there were Mongols, Russians, Chinese, Japanese, various other western groups in lesser numbers. Just about every religion was represented, it was a researcher's paradise for subjects. Ishii sought human experimentation and needed to find somewhere covert with maximum secrecy. He chose a place in the Nan Gang District of Beiyinhe village, roughly 70 kms southeast of Harbin. It was here and then he began human experimentation. One day in 1932, Ishii and the IJA entered the village and evacuated an entire block where Xuan Hua and Wu Miao intersected. They began occupying a multi-use structure that had been supporting 100 Chinese vendors who sold clothes and food to the locals. They then began drafting Chinese laborers to construct the Zhong Ma complex to house the “Togo Unit” named after the legendary admiral, Togo Heihachiro. The Chinese laborers were underpaid and under constant watch from Japanese guards, limiting their movement and preventing them from understanding what they were building, or what was occurring within the complex. The complex was built in under a year, it held 100 rooms, 3 meter high brick walls and had an electric fence surrounding the perimeter. One thousand captives at any given time could be imprisoned within the complex. To ensure absolute secrecy, security guards patrolled the complex 24/7. Saburo Endo, director of Operations for the Kwantung Army once inspected the Togo Unit and described it in his book “The Fifteen Years’ Sino-Japanese War and Me”, as such:
[It was] converted from a rather large soy sauce workshop, surrounded by high rammed earth wall. All the attending military doctors had pseudonyms, and they were strictly regulated and were not allowed to communicate with the outsiders. The name of the unit was “Tōgō Unit.” One by one, the subjects of the experiments were imprisoned in a sturdy iron lattice and inoculated with various pathogenic bacteria to observe changes in their conditions. They used prisoners on death row in the prisons of Harbin for these experiments. It was said that it was for national defense purposes, but the experiments were performed with appalling brutality.The dead were burned in high-voltage electric furnaces, leaving no trace.
A local from the region added this about the complex “We heard rumors of people having blood drawn in there but we never went near the place. We were too afraid. When the construction started, there were about forty houses in our village, and a lot of people were driven out. About one person from each home was taken to work on the construction. People were gathered from villages from all around here, maybe about a thousand people in all. The only things we worked on were the surrounding wall and the earthen walls. The Chinese that worked on the buildings were brought in from somewhere, but we didn’t know where. After everything was finished, those people were killed.”
Despite all the secrecy, it was soon discovered prisoners were being taken, primarily from the CCP and bandits who were being subjected to tests. One such test was to gradually drain a victim of blood to see at what point they would die. The unit drew 500 cc of blood from each prisoner every 3-5 days. As their bodies drew weaker, they were dissected for further research, the average prisoner lasted a maximum of a month. Due to the climate of Manchuria, it was soon established that finding methods to treat frostbite would benefit the Kwantung army. Ishii’s team gathered human subjects and began freezing and unfreezing them. Sometimes these experiments included observing test subjects whose limbs had been frozen and severed. The Togo team reported to General Okamura Yasuji, the deputy commander in chief of the Kwantung army from 1933-1934 that the best way to treat frostbite was to soak a limb in 37 degree water. According to the testimony of a witness named Furuichi at trial done in Khabarovsk , “Experiments in freezing human beings were performed every year in the detachment, in the coldest months of the year—November, December, January and February. The experimental technique was as follows: the test subjects were taken out into the frost at about 11 o’clock at night, compelled to dip their hands into a barrel of cold water and forced to stand with wet hands in the frost for a long time. Alternatively, some were taken out dressed, but with bare feet and compelled to stand at night in the frost during the coldest period of the year. When frostbite had developed, the subjects were taken to a room and forced to put their feet in water of 5 degrees Celsius, after which the temperature was gradually increased.”
Sergeant Major Kurakazu who was with Unit 731 later on in 1940 and taken prisoner by the Soviets in 1945 stated during the Khabarovsk trial , “I saw experiments performed on living people for the first time in December 1940. I was shown these experiments by researcher Yoshimura, a member of the 1st Division. These experiments were performed in the prison laboratory. When I walked into the prison laboratory, ve Chinese experimentees were sitting there; two of these Chinese had no fingers at all, their hands were black; in those of three others the bones were visible. They had fingers, but they were only bones. Yoshimura told me that this was the result of freezing experiments.”
According to Major Karasawa during the same trial Ishii became curious about using plague as a weapon of war and captured plague infected mice to test on subjects in the Zhong Ma Complex “Ishii told me that he had experimented with cholera and plague on the mounted bandits of Manchuria during 1933-1934 and discovered that the plague was effective.”
According to Lt General Endo Saburo’s diary entry on November 16th of 1933, at the Zhong Ma complex “The second squad which was responsible for poison gas, liquid poison; and the First Squad which was responsible for electrical experiments. Two bandits were used by each squad for the experiments.
- Phosgene gas—5-minute injection of gas into a brick-lined room; the subject was still alive one day aer inhalation of gas; critically ill with pneumonia.
- Potassium cyanide—the subject was injected with 15 mg.; subject lost consciousness approximately 20 minutes later.
- 20,000 volts—several jolts were not enough to kill the subject; injection of poison required to kill the subject.
- 5000 volts—several jolts were not enough; aer several minutes of continuous current, subject was burned to death.”
The Togo Unit established a strict security system to keep its research highly confidential. Yet in 1934, 16 Chinese prisoners escaped, compromising the Zhong Ma location. One of the guards had gotten drunk and a prisoner named Li smashed a bottle over his head and stole his keys. He freed 15 other prisoners and of them 4 died of cold, hunger and other ailments incurred by the Togo unit. 12 managed to flee to the 3rd route army of the Northeast Anti Japanese united Army. Upon hearing the horrifying report, the 3rd route army attacked the Togo unit at Beiyinhe and within a year, the Zhong Ma complex was exploded.
After the destruction of the Zhong Ma complex, Ishii needed a better structure. The Togo unit had impressed their superior and received a large budget. Then on May 30th of 1936 Emperor Hirohito authorized the creation of Unit 731. Thus Ishii and his colleagues were no longer part of the Epidemic Prevention Institute of the Army Medical School, now they were officially under the Kwantung Army as the Central Epidemic Prevention and Water Purification Department. Their new HQ was located in Pingfan, closer to Harbin. Their initial budget was 3 million yen for the personnel, 200-300 thousand yen per autonomous unit and 6 million yen for experimentation and research. Thus their new annual budget was over 10 million yen.
Pingfan was evacuated by the Kwantung army. Hundreds of families were forced to move out and sell their land at cheap prices. To increase security this time, people required a special pass to enter Pingfan. Then the airspace over the area became off-limits, excluding IJA aircraft, all violators would be shot down. The new Pingfan complex was within a walled city with more than 70 buildings over a 6 km tract of land. The complex’s huge size drew some international attention, and when asked what the structure was, the scientists replied it was a lumber mill. Rather grotesquely, prisoners would be referred to as “maruta” or “logs” to keep up the charade. Suzuki, a Japanese construction company back then, worked day and night to construct the complex.
Now many of you probably know a bit about Unit 731, but did you know it's one of countless units?
The Army’s Noborito Laboratory was established (1937)
The Central Epidemic Prevention and Water Purification Department of the North China Army/ Unit 1855 was established (1938)
The Central Epidemic Prevention and Water Purification Department of Central China/ Unit 1644 (1939)
Thee Guangzhou Epidemic Prevention and Water Purification Department of South China Army/ Unit 8604 (1942)
The Central Epidemic Prevention and Water Purification Department of the Southern Expeditionary Army/ Unit 9620 (1942).
There were countless others, detachments included Unit 1855 in Beijing, Unit Ei 1644 in Nanjing, Unit 8604 in Guangzhou, and later Unit 9420 in Singapore. All of these units comprised Ishii's network, which, at its height in 1939, oversaw over 10,000 personnel.
Victims were normally brought to Pingfan during the dead of night within crammed freight cars with number logs on top. They were brought into the building via a secret tunnel. According to a witness named Fang Shen Yu, technicians in white lab coats handled the victims who were tied in bags. The victims included anyone charge with a crime, could be anti-japanese activity, opium smoking, espionage, being a communist, homelessness, being mentally handicap, etc. Victims included chinese, Mongolians, Koreans, White Russians, Harbin’s jewish population and any Europeans accused of espionage. During the Khabarovsk trial, Major Iijima Yoshia admitted to personally subjecting 40 Soviet citizens to human experimentation. Harbin’s diversity provided great research data. Each prisoner was assigned a number starting with 101 and ending at 1500. Onec 1500 was reached, they began again at 101, making it nearly impossible to estimate the total number of victims. Since the complex had been labeled a lumber mill to the locals, most did not worry about it or were too afraid to do so. The prison's warden was Ishii’s brother Mitsuo who made sure to keep it all a secret.
Ethics did not exist within Ishii’s network of horrors. Everything was done efficiently in the name of science. Pingfang was equipped for disposing the evidence of their work in 3 large incinerators. As a former member who worked with the incinerators recalled “the bodies always burned up fast because all the organ were gone; the bodies were empty”. Human experimentation allowed the researchers their first chance to actually examine the organs of a living person at will to see the progress of a disease. Yeah you heard me right, living person, a lot of the vivisections were done on live people. As one former researcher explained "the results of the effects of infection cannot be obtained accurately once the person dies because putrefactive bacteria set in. Putrefactive bacteria are stronger than plague germs. So, for obtaining accurate results, it is important whether the subject is alive or not." Another former researcher said this “"As soon as the symptoms were observed, the prisoner was taken from his cell and into the dissection room. He was stripped and placed on the table, screaming, trying to fight back. He was strapped down, still screaming frightfully. One of the doctors stuffed a towel into his mouth, then with one quick slice of the scalpel he was opened up." Witnesses of some of these vivisections reported that victims usually let out a horrible scream when the initial cuts were made, but that the voice stops soon after. The researchers often removed the organ of interest, leaving others in the body and the victims usually died of blood loss or because of the removed organ. There are accounts of experiments benign carried out on mothers and children, because yes children were in fact born in the facilities. Many human specimens were placed in jars to be viewed by Tokyo’s army medical college. Sometimes these jars were filled with limbs or organs but some giant ones had entire bodies.
Vivisection was conducted on human beings to observe how disease affected each organ once a human dies. According to testimony given by a technician named Ogawa Fukumatsu “I participated in vivisections. I did them every day. I cannot remember the amount of people dissected. At first, I refused to do it. But then, they would not allow me to eat because it was an order; gradually I changed.” Another technician Masakuni Kuri testified “I did vivisection at the time. Experiments were conducted on a Chinese woman with syphilis. Because she was alive, the blood poured out like water from a tap.”
A report done by Shozo Kondo studied the effects of bubonic plague on humans. The number of subjects was 57 with age ranging from toddlers to 80 years old with mixed gender. The study used fleas carrying plague that were dispersed upon the local population in June of 1940 at Changchun. 7 plague victims were Japanese residents. The report stated the plague spread because of lack of immunity by the townspeople. Subjects' survival time ranged from 2-5 days, with only 3 surviving 12, 18 and 21 days. The subjects were infected with Glandular, Cutaneous or Septicemic plague, but most had the Glandular variety.
In addition to the central units of Pingfang were others set up in Beijing, Nanjing, Guangzhou and Singapore. The total number of personnel was 20,000. These satellite facilities all had their own unique horror stories. One was located in Anda, 100km from Pingfang where outdoor tests for plague, cholera and other pathogens were down. They would expose human subjects to biological bombs, typically by putting 10-40 people in the path of a biological bomb. A lot of the research was done to see the effective radius of the bombs, so victims were placed at different distances. At Xinjing was Unit 100 and its research was done against domesticated animals, horses particularly. Unit 100 was a bacteria factory producing glanders, anthrax and other pathogens. They often ran tests by mixing poisons with food and studied its effects on animals, but they also researched chemical warfare against crops. At Guangzhou was unit 8604 with its HQ at Zhongshan medical university. It is believed starvation tests ran there, such as the water test I mentioned. They also performed typhoid tests and bred rats to spread plague. Witness testimony from a Chinese volunteer states they often dissolved the bodies of victims in acid. In Beijing was Unit 1855 which was a combination of a prison and experiment center. They ran plague, cholera and typhus tests. Prisoners were forced to ingest mixtures of germs and some were vaccinated against the ailments. In Singapore after its capture in February of 1942 there was a secret laboratory. One Mr. Othman Wok gave testimony in the 1990s that when he was 17 years old he was employed to work at this secret lab. He states 7 Chinese, Indian and Malay boys worked in the lab, picking fleas from rats and placing them in containers. Some 40 rat catchers, would haul rats to the lab for the boys to do their work. The containers with fleas went to Japanese researchers and Othman says he saw rats being injected with plague pathogens. The fleas were transferred to kerosene cans which contained dried horse blood and an unidentified chemical left to breed for weeks. Once they had plague infected fleas in large quantity Othman said "A driver who drove the trucks which transported the fleas to the railway station said that these bottles of fleas were sent off to Thailand." If this is true, it gives evidence to claims Unit 731 had a branch in Thailand as well. Othman stated he never understood or knew what was really going on at the lab, but when he read in 1944 about biological attacks on Chongqing using fleas, he decided to leave the lab. Othman states the unit was called Unit 9240.
As you can imagine rats and insects played a large role in all of this. They harvested Manchuria rat population and enlisted schoolchildren to raise them. In the 1990s the Asahi Broadcasting company made a documentary titled “the mystery of the rats that went to the continent”. It involved a small group of high school children in Saitama prefecture asked local farmers if they knew anything about rat farming during the war years. Many stated everybody back then was raising rats, it was a major source of income. One family said they had rat cages piled up in a shed, each cage built to carry 6 rat, but they had no idea what the rats were being used for. Now hear this, after the war, the US military kept these same families in business. The US army unit 406 which was established in Tokyo to research viruses wink wink, would often drive out to these farms in their american jeeps collecting rats.
Getting fleas was a much tricker task. One method was taking older Chinese prisoners and quarantining them with clothes carrying flea or flea eggs and allowing them to live in isolated rooms to cultivate more fleas. These poor guys had to live in filth and not shave for weeks to produce around 100 fleas a day. Now Unit 731 dealt with numerous diseases such as Cholera. Some experiments used dogs to spread cholera to villages. They would steal dogs from villages, feed them pork laced with cholera germs and return them to the villages. When the disease finished incubating the dogs would vomit and other dogs would come and eat the vomit spread it more and more. The dogs were also stricken with diarrhea and the feces spread it to other dogs as well. 20% of the people in villages hit by this died of the disease. Former army captain Kojima Takeo was a unit member involved in a Cholera campaign and added this testimony "We were told that we were going out on a cholera campaign, and we were all given inoculations against cholera ten days before starting out. Our objective was to infect all the people in the area. The disease had already developed before we got there, and as we moved into the village everyone scattered. The only ones left were those who were too sick to move. The number of people coming down with the disease kept increasing. Cholera produces a face like a skeleton, vomiting, and diarrhea. And the vomiting and defecating of the people lying sick brought flies swarming around. One after the other, people died."
I've mentioned it a lot, Plague was a staple of Unit 731. The IJA wanted a disease that was fast and fatal, Cholera for instance took about 20 days, plague on the other hand starts killing in 3 days. Plague also has a very long history of use going back to the medieval times. It was one of the very first diseases Ishii focused on. In october of 1940 a plague attack was conducted against the Kaimingjie area in the port city of Ningbo. This was a joint operation with Unit 731 and the Nanjing based Unit 1644. During this operation plague germs were mixed with wheat, corn, cloth scraps and cotton and dropped from the air. More than 100 people died within a few days of the attack and the affected area was sealed off from the public until the 1960s.
Another horrifying test was the frostbite experiments. Army Engineer Hisato Yoshimura conducted these types of experiments by taking prisoners outside, dipping various appendages into water of varying temperatures and allowing the limbs to freeze. Once frozen, Yoshimura would strike their affected limbs with a short stick and in his words “they would emit a sound resembling that which a board gives when it is struck”. Ice was then chipping away with the affected area being subjected to various treatments, such as being doused in water, exposed to heat and so on. I have to mentioned here, that to my shock there is film of these specific frostbite experiments and one of our animators at Kings and Generals found it, I have seen a lot of things in my day, but seeing this was absolute nightmare fuel. If you have seen the movie or series Snowpiercer, they pretty much nail what it looked like.
Members of Unit 731 referred to Yoshimura as a “scientific devil” and a “cold blooded animal” because he would conduct his work with strictness. Naoji Uezono another member of Unit 731, described in a 1980s interview a disgusting scene where Yoshimura had "two naked men put in an area 40–50 degrees below zero and researchers filmed the whole process until [the subjects] died. [The subjects] suffered such agony they were digging their nails into each other's flesh". Yoshimuras lack of any remorse was evident in an article he wrote for the Journal of Japanese Physiology in 1950 where he admitted to using 20 children and 3 day old infant in experiments which exposed them to zero degree celsius ice and salt water. The article drew criticism and no shit, but Yoshimura denied any guilt when contacted by a reporter from the Mainichi Shimbun. Yoshimura developed a “resistance index of frostbite” based on the mean temperature of 5 - 30 minutes after immersion in freezing water, the temperature of the first rise after immersion and the time until the temperature first rises after immersion. In a number of separate experiments he determined how these parameters depended on the time of day a victim's body part was immersed in freezing water, the surrounding temperature and humidity during immersion, how the victim had been treated before the immersion ("after keeping awake for a night", "after hunger for 24 hours", "after hunger for 48 hours", "immediately after heavy meal", "immediately after hot meal", "immediately after muscular exercise", "immediately after cold bath", "immediately after hot bath"), what type of food the victim had been fed over the five days preceding the immersions with regard to dietary nutrient intake ("high protein (of animal nature)", "high protein (of vegetable nature)", "low protein intake", and "standard diet"), and salt intake.
Members of Unit 731 also worked with Syphilis, where they orchestrated forced sex acts between infected and noninfected prisoners to transmit the disease. One testimony given by a prisoner guard was as follows “Infection of venereal disease by injection was abandoned, and the researchers started forcing the prisoners into sexual acts with each other. Four or five unit members, dressed in white laboratory clothing completely covering the body with only eyes and mouth visible, rest covered, handled the tests. A male and female, one infected with syphilis, would be brought together in a cell and forced into sex with each other. It was made clear that anyone resisting would be shot.” After victims were infected, they would be vivisected at differing stages of infection so that the internal and external organs could be observed as the disease progressed. Testimony from multiple guards blamed the female victims as being hosts of the diseases, even as they were forcibly infected. Genitals of female prisoners were infected with syphilis and the guards would call them “jam filled buns”. Even some children were born or grew up in the walls of Unit 731, infected with syphilis. One researcher recalled “one was a Chinese women holding an infant, one was a white russian woman with a daughter of 4 or 5 years of age, and the last was a white russian women with a boy of about 6 or 7”. The children of these women were tested in ways similar to the adults.
There was also of course rape and forced pregnancies as you could guess. Female prisoners were forced to become pregnant for use in experiments. The hypothetical possibility of transmission from mother to child of diseases, particularly syphilis was the rationale for the experiments. Fetal survival and damage to the womans reproductive organs were objects of interest. A large number of babies were born in captivity and there had been no accounts of any survivor of Unit 731, children included. It is suspected that the children of the female prisoners were killed after birth or aborted. One guard gave a testimony “One of the former researchers I located told me that one day he had a human experiment scheduled, but there was still time to kill. So he and another unit member took the keys to the cells and opened one that housed a Chinese woman. One of the unit members raped her; the other member took the keys and opened another cell. There was a Chinese woman in there who had been used in a frostbite experiment. She had several fingers missing and her bones were black, with gangrene set in. He was about to rape her anyway, then he saw that her sex organ was festering, with pus oozing to the surface. He gave up the idea, left and locked the door, then later went on to his experimental work.”
In a testimony given on December 28 by witness Furuichi during the Khabarovsk Trial, he described how “a Russian woman was infected with syphilis to allow the scientists to and out how to prevent the spread of the disease. Many babies were born to women who had been captured and become experimental subjects. Some women were kidnapped while pregnant; others became pregnant aer forced sex acts in the prisons, enabling researchers to study the transmission of venereal disease
Initially Unit 731 and Unit 100 were going to support Japan's Kantokuen plan. The Kantokuen plan an operation plan to be carried out by the Kwantung army to invade the USSR far east, capitalizing on the success of operation barbarossa. Unit 731 and 100 were to prepare bacteriological weapons to help the invasion. The plan was created by the IJA general staff and approved by Emperor Hirohito. It would have involved three-steps to isolate and destroy the Soviet Army and occupy the eastern soviet cities over the course of 6 months. It would have involved heavy use of chemical and biological weapons. The Japanese planned to spread disease using three methods; direct spraying from aircraft, bacteria bombs and saboteurs on the ground. This would have included plague, cholera, typhus and other diseases against troops, civilian populations, livestocks, crops and water supplies. The main targets were Blagoveshchensk, Khabarovsk, Voroshilov, and Chita. If successful the Soviet Far East would be incorporated into Japan’s greater east asia co-prosperity sphere. Within Kantokuen documents, Emperor Hirohtio instructed Ishii to increase production rate at the units, for those not convinced Hirohito was deeply involved in some of the worst actions of the war. Yet in the end both Emperor Hirohito and Hideki Tojo pulled their support for the invasion of the USSR and opted for the Nanshin-ron strategy instead.
On August 9th of 1945 the Soviet Union declared war on Japan and invaded Manchuria. In response, the Japanese government ordered all research facilities in Manchuria to be destroyed and to erase all incriminating materials. A skeleton crew began the liquidation of unit 731 on August 9th or 10th, while the rest of the unit evacuated. All test subjects were killed and cremated so no remains would be found. The design of the facilities however, made them hard to destroy via bombing, several parts of the buildings left standing when the Soviets arrived. While most of the unit's staff managed to escape, including Ishii, some were captured by the soviets. Some of these prisoners told the Soviets about the atrocities committed at Pingfang and Changchun. At first the claims seemed so outrageous, the Soviets sent their own Biological Weapons specialists to examine the ruins of Ping Fang. After a thorough investigation, the Soviet experts confirmed the experiments had been done there.
The real soviet investigation into the secrets of Unit 731 and 100 began in early 1946, thus information was not readily available during the Tokyo Tribunal. Both the Americans and SOviets had collected evidence during the war that indicated the Japanese were in possession of bacteriological weapons though. Amongst the 600,000 Japanese prisoners of war in the USSR, Major General Kiyoshi Kawashima and Major Tomoio Karasawa would become essential to uncovering the Japanese bacteriological warfare secrets and opening the path to hold the Khabarovsk trial.
The Soviets and Americans spent quite a few years performing investigations, many of which led to no arrests. The major reason for this was similar to Operation Paperclip. For those unaware, paperclip was a American secret intelligence program where 1600 German scientists were taken after the war and employed, many of whom were nazi party officials. The most famous of course was Wernher von Braun. When the Americans looked into the Japanese bacteriological work, they were surprised to find the Japanese were ahead of them in some specific areas, notably ones involving human experimentation. General Charles Willoughby of G-2 american intelligence called to attention that all the data extracted from live human testing was out of the reach of the USA.
By the end of 1947, with the CCP looking like they might defeat Chiang Kai-Shek and the Soviet Union proving to be their new enemy, the US sought to form an alliance with Japan, and this included their Bacteriological specialists. From October to December, Drs Edwin Hill and Joseph Victor from Camp Detrick were sent to Tokyo to gather information from Ishii and his colleagues. Their final conclusion laid out the importance of continuing to learn from the Japanese teams, and grant them immunity. The British were also receiving some reports from the Americans about the Japanese Bacteriological research and human experimentation. The British agreed with the Americans that the information was invaluable due to the live human beings used in the tests. The UK and US formed some arrangements to retain the information and keep it secret. By late 1948 the Tokyo War Crimes Trial was coming to an end as the cold war tension was heating up in Korea, pushing the US more and more to want to retain the information and keep it all under wraps.
With formal acceptance, final steps were undertaken, much of which was overseen by General Douglas MacArthur. On May 6, 1947, Douglas MacArthur wrote to Washington that "additional data, possibly some statements from Ishii probably can be obtained by informing Japanese involved that information will be retained in intelligence channels and will not be employed as 'War Crimes' evidence.”
Ishii and his colleagues received full immunity from the Tokyo War Crimes Trial. Ishii was hired by the US government to lecture American officers at Fort Detrick on bioweapons and the findings made by Unit 731. During the Korean War Ishii reportedly traveled to Korea to take part in alleged American biological warfare activities. On February 22nd of 1952, Ishiiwas explicitly named in a statement made by the North Korean FOreign Minister, claiming he along with other "Japanese bacteriological war criminals had been involved in systematically spreading large quantities of bacteria-carrying insects by aircraft in order to disseminate contagious diseases over our frontline positions and our rear". Ishii would eventually return to Japan, where he opened a clinic, performing examinations and treatments for free. He would die from laryngeal cancer in 1959 and according to his daughter became a Roman Catholic shortly before his death.
According to an investigation by The Guardian, after the war, former members of Unit 731 conducted human experiments on Japanese prisoners, babies, and mental patients under the guise of vaccine development, with covert funding from the U.S. government. Masami Kitaoka, a graduate of Unit 1644, continued performing experiments on unwilling Japanese subjects from 1947 to 1956 while working at Japan's National Institute of Health Sciences. He infected prisoners with rickettsia and mentally ill patients with typhus. Shiro Ishii, the chief of the unit, was granted immunity from prosecution for war crimes by American occupation authorities in exchange for providing them with human experimentation research materials. From 1948 to 1958, less than five percent of these documents were transferred to microfilm and stored in the U.S. National Archives before being shipped back to Japan.
