Unit 731 was a unit of theImperial Japanese Army that performedbiological andchemical warfare research and development. Its members did deadly experiments on humans during theSecond Sino-Japanese War (World War II). It was responsible for some of the most notoriouswar crimes committed by the armed forces of Imperial Japan. It has been called one of the worst atrocities in World War II.[1]
The unit was originally based in the Pingfang district ofHarbin, the largestcity in thepuppet state ofManchukuo. The location changed in 1945, when theSoviet Unioninvaded in what would be known as the Soviet Invasion ofManchuria of 1945.
It was active throughoutChina andSoutheast Asia.Estimates say that up to half a million people were killed by Unit 731 and its related programs, on the orders of the camp's directorShirō Ishii.
Unit 731 was officially known as theEpidemic Prevention and Water Purification Department of the Kwantung Army. It was originally set up by the military police of theEmpire of Japan. Later, Unit 731 was taken over and commanded until the end of the war by General Shirō Ishii, a combat medic officer in the Kwantung Army.
The program received generous support from the Japanese government until the end of the war in 1945. Unit 731 and other units operatedbiological weapon production, testing, deployment, and storage facilities. They routinely conducted tests on human beings (who were internally referred to as "logs"). Additionally, biological weapons were tested in the field on cities and towns in China.
Unit 731researchersarrested by Soviet forces were put ontrial. However, members who were captured by theUnited States were secretly given immunity in exchange for thedata gathered during their experiments.[2] The Americans co-opted the researchers' bioweapons information and experience for use in their own biological warfare program, much as they had done withGerman researchers inOperation Paperclip.[3]
In 2002 a Tokyo court admitted that Japan had engaged ingerm warfare and killed thousands of Chinese civilians.[1][4] This was the first time that the Japanese government had acknowledged this publicly.[1][4]
