The unit was commanded by Major General Sato Shunji, a physician. It was staffed by a total of 800 personnel: 100 commissioned officers (many with medical or scientific backgrounds), 200 medical and scientific researchers, and 500 soldiers and noncommissioned officers.
In 1994, the "Japan's China Invasion Factual Investigation Record China Entourage" confirmed the existence of the unit and collected testimony from former members and victims. Shigeru Maruyama, a former member of the unit said that one experiment involved starving prisoners to death and talked of seeing victims being operated on almost every day.
^Yamada (山田乙三), Otozō, ed. (1950), Materials on the Trial of Former Servicemen of the Japanese Army Charged with Manufacturing and Employing Bacteriological Weapons / Documents relatifs au procès des anciens Militaires de l'Armée Japonaise accusés d'avoir préparé et employé l'Arme Bactériologique / 細菌戦用兵器ノ準備及ビ使用ノ廉デ起訴サレタ元日本軍軍人ノ事件ニ関スル公判書類 / 前日本陸軍軍人因準備和使用細菌武器被控案審判材料, Moscow: Foreign Languages Publishing House, p. 524, OCLC24964936