The Beginning
A top-notch medical research program coupled with the Japanese Empire's eagerness to expand paved the way for the development of Shirō Ishii's biochemical warfare program.
Initial Strides into Biochemical Warfare
Shiro Ishii presented his idea of establishing a biological experimentation facility in Manchuria to the Japanese Army. Colonel Koizumi greenlit the project, and several chemical weapons such as chlorine gas were developed. The newly created toxins were used several times on the city of Harbin. Harbin served as Unit 731's base of operations until 1945, and was primarily used for human experimentation.
"The life expectancy of prisoners at the [Zhongma Fortress] was a maximum of one month." -Ziyang Wang, former prisoner at Zhongma Fortress