The west often dismissed the Khabarovsk War Crimes Trial as "Communist Propaganda." However, it was the first time the scientists from the "Epidemic Prevention and Water Purification Department" of the Imperial Japanese Army(IJA) came forward with the crimes they committed during World War 2. To confuse others about what their mission is, they frequently use the name, "Water Supply and Prophylaxis Administration of the Kwantung Army," or "Hippo-Epizootic Administration of the Kwantung Army."
Although it was established in 1935-1936, after 1941, after the Nazi Germany attack on the U.S.S.R. and the world was engaged in a full-blown war, the institutions were renamed to be Unit 100 and Unit 731, and had more specific tasks and employed thousands of scientists as stated previously.
The trial made clear to the public how these biological and chemical weapon divisions worked for the IJA at the time. Unit 100 and Unit 731 were both staffed by leading bacteriologists of Japan at the time. They had numerous branches located in strategical areas. The Japanese Army Command funded both units for their research and development, which made the units direct subordinates to the Commander-in-Chief of the IJA.
The Eight Divisions of Unit 731
The 1st Division bred germs of plague, cholera, gas gangrene, anthrax, typhoid, paratyphoid fever, and other diseases in bacteriological warfare. The 2nd Division was more of an experimental division that conducted tests of unique weapons to disseminate germs. They worked on sprayers in the form of fountain pens and walking stickers, porcelain aerial bombs, and other weapons for the sabotage groups. They also controlled an aircraft unit with specially equipped planes and a proving ground near Anta Station (where they tested the effects of certain biological bombs). The 2nd Division also engaged in the cultivation and breeding of parasites designed to cause plague epidemics.
Although the Unit 731 claimed that they were working at the "Epidemic Prevention and Water Purification Department" of the IJA, it is known that out of the eight divisions of Unit 731, only one of them(the 3rd Division) occupied themselves with the research of water supply and prophylaxis. But even so, that Division manufactured cases for bacteria shells known as "Ishii aerial bombs," which were used to drop plague-infected fleas from aircraft.
The 4th Division was a "factory" for mass production of germs and various bacteria.
There was also a division of the eight that was called the "Training and Education" Division. It trained its soldiers on skills related to the use of bacteriological weapons for combat units and sabotage groups.
Another division bred fleas, rats, mice, and other rodents to spread disease microbes, including plague, cholera, typhoid, and other germs for the mass genocide. According to a witness named Morita, Branch 543 in Hailar of Unit 731 had about 13,000 rats to spread microbe diseases.