Unit 731

Unit 731 was a covert biological warfare research and development unit of the Imperial Japanese Army that undertook lethal human experimentation during the Second Sino-Japanese War (1937–1945) and World War II. It was responsible for some of the most notorious war crimes carried out by Japanese personnel. Officially known by the Imperial Japanese Army as the Kempeitai Political Department and Epidemic Prevention Research Laboratory, it was initially set up as a political and ideological section of the Kempeitai military police of pre-Pacific War Japan. It was meant to counter the ideological or political influence of enemies, and to reinforce the ideology of military units.
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