Special Research Units

The Epidemic Prevention and Water Purification Department was a department of the Imperial Japanese Army from 1936 to the dissolution of the Army in 1945. While its public mission was to prevent the spread of disease and monitor water supply, several field armies also assigned units the mission of manufacturing biological weapons. Many units also performed human experimentation.

The department was organized under the following system:

The 1996 book Germ Warfare Units (細菌戦部隊) contains testimonies that all of these units engaged in biological weapon development.

Each office was equipped with water purification facilities and trucks to transport water to where it was needed. The water filtration equipment was designed by Shirō Ishii of Unit 731.

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