Unit 731 (731 部隊, Nana-san-ichi butai) was a covert biological and chemical 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.
From 1936 to 1942 approximately 12,000 men, women and children were murdered in Unit 731, but the atrocities committed there were physically worse than in the Nazi death camps: their suffering lasted much longer, and not one prisoner survived.
Infected clothing and food supplies were also dropped. Villages and whole towns were afflicted with cholera, anthrax and the plague, which between them killed over the years an estimated 400,000 Chinese.
The trial of captured Japanese perpetrators was held in Khabarovsk in December 1949. The Japanese doctors and army commanders who had perpetrated the Unit 731 atrocities and germ warfare experiments received sentences from the Khabarovsk court ranging from two to 25 years in a Siberian labor camp. After World War II, the Soviet Union built a biological weapons facility in Sverdlovsk using documentation captured from Unit 731 in Manchuria.
Unit 731 leaders arrested by the American occupation authorities at the end of World War II received immunity in 1949 in exchange for the data based on human experimentation. Some former members of Unit 731 became part of the Japanese medical establishment. Dr. Masaji Kitano led Japan’s largest pharmaceutical company, the Green Cross. Others headed U.S.-backed medical schools or worked for the Japanese health ministry. Shiro Ishii in particular moved to Maryland to work on bio-weapons research.
One of the victims vivisected in a temple was a young woman about 20 years old, and villagers still remember her scream, “I am not dead yet, don’t cut me open!”
Toshimi Mizobuchi: “From Japan’s point of view, they were criminals who had been sentenced to death. We were merely acting as the executioners. I am proud of what we did. If I was younger, I’d consider doing it all again because it was an interesting Unit.”
Yoshio Shinozuka: “Looking at your faces [addressing Chinese audience in Harbin], I am deeply sorry for what I did. I committed such atrocities. I realise that simply bowing my head and saying sorry is not enough to earn your forgiveness.”