Page 53 - Unit 731

Q: Would it not be difficult to produce typhus organisms on a large scale?
A: If you could produce a lot of lice you might be able to produce a lot of typhus. German and Polish vaccine is prepared from lice. Trouble with lice is that you have to have human infectious blood
to infect the lice. Weil’s disease is produced in the same manner and it is very hard to get large quantities. If a country was rich enough, it might be able to make that disease a dangerous weapon.
Q: Was any research conducted on BW against food plants?
A: We did not do any experiments on it. Our work was to protect the soldiers.
Q: Did anyone else concern themselves with BW against crop plants?
A: I do not know.
Q: Were you concerned with BW agents against animals?
A: We did not do any experiments on large animals. We used small animals as test animals. Besides, we had no veterinarians.
Q: Did veterinary laboratories do any research on BW?
A: I do not know. It was such a secret that there was no communication between units. Even personnel working on experiments in my unit did not know what they were working on. Only myself,
Colonel MASUDA, and one or two other persons know.
Q: Who were the other persons?
A: There were some who suspected what was going on, but did not know. Colonel MASUDA, Tomosada, and myself know.
Q: What section of the BW institute did the BW work?
A: When those experiments came up, a number of men from each group were picked out to do the work. They were only together temporarily and were disbanded when the experiment was
completed.
Q: Were all the people in such groups informed of the nature of the work?
A: They were not informed of what they were doing. They protested that they could not carry on with their own experiments and that their regular work was being interfered with.
Q: Would not more progress have been made if those working on the experiment had been told what it was all about?
A: If they had known what they were working on they would have shrunk up from fright and asked for more pay. They were not well-trained men
Q: A soldier is a soldier and could you not have ordered them to do the work?
A: They were not soldiers. They were reservists. Those in the branch units were soldiers, but not those in the main unit. I could not order them.
Q: How much research cooperation was given by the Navy on BW?
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A: There was no cooperation whatsoever. [See Fig. 35.]
At the time of this interrogation, the Tokyo Trials had started. Whether to work with the US Army or not, and in what ways, were key factors that would
impact the destiny of Shirō Ishii and his team members in Unit 731. Ishii was receiving a high volume of interrogation in the Trials. The investigation by
the US Army affected Shirō Ishii, but he did not deny or fully admit his responsibility in Unit 731.
In order to conceal his crimes and avoid trial and sentencing, Ishii deflected the US Army interrogators. Under investigation, he covered up the facts of
Japanese biological warfare, biological weapons, and human experimentation and only admitted involvement in bacterial and preventive medical research.
At the same time, he led Thompson into the sensitive topic of Soviet biological warfare preparation, with which he tried to complicate the issue of
biological warfare. Thompson’s report above shows the US Army failed to gain what was expected from Shirō Ishii.
Thompson’s Assessment of Ishii
Shirō Ishii attempted to deflect Thompson’s first investigation, however, his plan to escape the Tokyo Trials was known to Thompson. In subsequent
reports, Thompson said:
The information regarding Japanese BW activities obtained from presumably independent sources was consistent to the point where it seems that the informants had been instructed as to the amount
and nature of information that was to be divulged under interrogation.
All information was presumably furnished from memory since all records are said to have been destroyed in accordance with directives of the Japanese Amy. Yet, some of the information,
especially sketches of the bombs, was in such detail as to question the contention that all documentary evidence had been destroyed. It was evident throughout the interrogations that it was the desire
of the Japanese to minimise the extent of their activities in BW, especially the effort devoted to offensive research and development. 14
In general, the previous three points by Thompson are accurate. He discovered that immediately prior to the beginning of war crimes investigation, Ishii
and other members secretly agreed not to reveal the truth.
During the US investigation into Japanese biological warfare, Ishii’s assistant, Ryoichi Naito, who had been in charge of the disease prevention centre,
took action to contact the US Army. During negotiations with the Army, Naito revealed details heard from the US Army to other Unit 731 members.
Thompson doubted the validity of the destruction of all information by the Japanese Army, and he believed Ishii hid facts about the creation of biological
weapons. Based on the preceding narrative, Thompson was dissatisfied with what he heard, and he then aimed to interrogate Masaji Kitano, who had just
escaped to Japan from China. Ishii and Kitano were core members of Unit 731, and Thompson’s intent was to gain as much evidence as he could from
major participants.
The Unit 731 facilities had vanished, but once its members escaped to Japan, they set up operation headquarters in Noma Shrine (野间神社) in
Kanazawa. Most of the research information bought from Unit 731 in Harbin was kept in this Noma Shrine. The order for secrecy given by Shirō Ishii
remained in effect among former members, and as commander, he used his position to fabricate the same narrative for other members. At the same time, he
requested members investigate the information sought by the US Army. While he did not fully understand the aim of the US investigation, he feared he
would be sent to the Tokyo Trials if the US Army did not believe his testimony.
Completion of Thompson’s Report
From 5 February to 11 March 1946, Thompson conducted interrogation of Shirō Ishii and other members and completed his ‘Report about Japanese
15
Biological Weapons’ on 31 May 1947. The forty-eight-page report includes Shirō’s biography, educational background, and record of overseas trips for
biological warfare research, as well as the organisation, management, and duties of Unit 731.
Through ‘The Thompson Report’, Shirō Ishii provided useful material that allowed the US to learn about human resource management, organisation,
research areas, and progress, as well as bacteriological warfare and human experimentation. He responded more fully to Thompson’s investigation than he
did to Sanders. At the beginning, he refused to discuss bacteriological warfare and human experimentation, but later he welcomed Thompson’s questions
regarding these sensitive issues. The reason for his change of attitude remains unknown. In my opinion, he could have known that ‘the investigation would
not be used as evidence in war trials’. 16
The following are Shirō Ishii’s points as reported by Thompson:
Failure to fully utilise Japanese scientific capability by restriction of BW research and development to the military with lack of cooperation between the military services precluded progress toward
development of BW into a practical weapon. Had a practical BW weapon been achieved, it is unlikely that Japan would have resorted to its use because of fear retaliation by means of chemical
warfare. Insofar as could be learned, Japan had no information of American activity in BW. 17
According to current information, research on biological weapons by Unit 731 was supported by the Japanese Military Department, the Japanese Army,
Kanto Army, and some other institutions, such as Tokyo Army Surgeon Hospital School, Kanto Army Unit 100, and Unit 516. At the same time, Tokyo
Imperial University, Kyoto Imperial University, and some other Japanese medical schools provided support and assistance to Unit 731, which allowed the
Unit to build powerful connections with top research institutions from military and medical fields. In ‘The Thompson Report’, Thompson revealed his lack
of understanding the truth of Japanese research on biological weapons, and at the same time admitted that the US was involved in the same kind of
research.
Investigation by Norbert Fell