The Japanese military authorities assembled 2,600 technicians and research workers to serve in the unit with scholars of the medical school of Kyodo Imperial University as its backbone.
石井四郎在日本，集合了二千六百名以京都帝大醫學部為核心的醫師、研究員及助手，秘密的在七三一部隊中，從事細菌戰的研究。