Page 51 - Unit 731

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Investigation, Cover-up, and Exchange

With the surrender of Japan announced by Emperor Hirohito, the Second World War came to an official end on 15 August 1945. US President Harry S.
Truman appointed Gen. Douglas MacArthur as Supreme Commander for the Allied Powers, and MacArthur accepted the surrender of Emperor Hirohito
aboard the USS Missouri.
During this period, before the start of the Cold War and the spread of Communist ideology, in order to control post-war Japan under the US’s choice of
ideological and political systems, the US took the lead in the International Military Tribunal for the Far East (also known as the Tokyo Trials) slated to try
Japanese war criminals. Beginning in September 1945, the US Army initiated investigation into Japanese biological warfare. The investigation ended
November 1948. Over four years, the US Army successfully enacted a secret agreement with the Japanese government allowing members of Unit 731 to
avoid trial.
At the end of the Second World War, members of Unit 731, including Shirō Ishii and Masaji Kitano, returned to Japan where many of them lived
secretly, changed their names, or faked their deaths to escape trial. The US Army sought statistics and data on Japanese biological warfare and experiments
carried out by Unit 731, therefore, prior to the Tokyo Trials, the US intelligence agency investigated Ishii, Kitano, and other members of the unit. At least
twenty-five members were tried by the US Army; however, Ishii and others were exempted from trial.

Tracking Shirō Ishii
The US Intelligence Agency paid primary attention to the founder of Unit 731, Shirō Ishii, rating him the most wanted person by the US authorities. The
Second Division of the General Staff Headquarters in Tokyo had assigned intelligence agents to track him down for a long time.

Fraudulent Death of Shirō Ishii
Three months before the Tokyo Trials, Ishii faked his death to evade trial, but twenty days later, the US Intelligence Agency uncovered his deception.
According to the information collected from the Intelligence Agency: ‘… on December 3, 1945, an informer of the US Army reported that Shirō Ishii had
arranged a fake funeral for himself at his hometown Chiyoda village at Sanbugun, Chiba on November 10, 1945. He, however, remained hidden with the
help of the head villager. Shirō Ishii was the Lieutenant General and head of Ishii Division and was in charge of human experimentation during the war’. 1
More information on Ishii was contained in a US Army memo dated 3 December:

The biological warfare division was established in Harbin under the command of Shirō Ishii. In December 1944, a large-scale bacteria laboratory had successfully cultured Yersinia pastis in Harbin.
This bacteria was released throughout Manchuria. In Shenyang, some US POWs were injected with Yersinia pestis. In order to observe the experiment results, the biological warfare division released
infected mice in Shenyang and other areas to create large-scale plague. After these experiments, Shirō Ishii noted the need to culture Yersinia pestis for use in warfare. When Japan was defeated, the
Japanese Army destroyed laboratories as well as abundant important information, facilities and hundreds of ‘marutas’ [prisoners]. Ishii’s biological warfare division had cooperated with the
Department of Medicine in the University of Tokyo. 2
The US Army documented Ishii’s activities, especially his involvement in the Harbin laboratory, human experimentation, and biological warfare, as well as
his collaboration with the University of Tokyo. This information had reached the core of Unit 731—human experimentation and biological warfare.
Information from the Intelligence Agency: Discovery of Shirō Ishii

A US Army record, dated 28 December 1945, states: ‘Shirō Ishii left Harbin with about $1 million cash. Shirō Ishii was suspected by the Intelligence
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Agency for not being arrested as war criminal’. Another US Army record, dated 7 January 1946, states:
According to comment from the United States Department of Defense made on January 6, 1946, Shirō Ishii committed biological experiments in Manchuria and should be arrested and interrogated.
The record from the Secret Intelligence Service and military could not reveal the location of Shirō Ishii, and it did not request the Japanese government to arrest Shirō Ishii for the US Army. 4
On 7 January 1946, members of the US Intelligence Agency interviewed Ralph Teatsorth and S. E. Whitesides of the United Forces Association in the
Tokyo Broadcasting Building. Teatsorth provided information on ‘Shirō Ishii’s involvement in plague injection of American and Chinese POWs’, and
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Whitesides presented proof of Ishii’s involvement in biological warfare and the Unit 731 Bacteria Division. Neither man knew Ishii’s location. Four days
after the release of Teatsorth’s information, on 11 January, he interrogated the second in command of Unit 731, Masaji Kitano, who provided further
information about biological experiments and bacteria bombs. The US Intelligence Agency put great effort into tracing Shirō Ishii in order to collect details
on human experimentation, which made Ishii the man most wanted by the Agency.
On 8 January 1946, an informant provided clues about Shirō Ishii’s location: ‘Shirō Ishii went to the Kanazawa area. Professor Tachio Ishikawa (石川
太刀雄) from the Department of Pathology in Kanazawa University knew Ishii’s location’. 6
The following day, the US Army received information from the Central Liaison Office in Tokyo: ‘The Japan Imperial Government would like to turn
over Shirō Ishii to Tokyo for interrogation by the Supreme Commander for the Allied Powers. When Shirō Ishii arrived in Tokyo, the Imperial Government
would contact the Allied Powers as soon as possible. If Ishii did not arrive by midnight January 16, 1946, the Imperial Government would provide a
detailed report explaining Ishii’s location and reason for his absence in order to suggest his arrival date’. 7
At that time, neither the US Army nor Japanese official agencies officially knew Ishii’s whereabouts, but the possibility of the Japanese government’s
intentional cover-up should not be ignored.
The US Army stated its intentions back on 2 January 1946: ‘The Secret Intelligence Service and military requested information related to biological
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warfare and wished to collect further valuable information’. Yet weeks had passed with no results as the prime target remained in hiding.
On 19 January 1946, the International Military Tribunal for the Far East was established and announced its charter. The Tokyo Trials were about to
start, and the deadline of 16 January, as set by the Japanese government, had passed. The Tokyo Central Office contacted Professor Tachio Ishikawa
regarding Ishii’s location without results. The Intelligence Agency suggested that the Tokyo Central Office failed to provide the location of Shirō Ishii and