Unit Ei 1644 ( ) — also known as Unit 1644 , Detachment Ei 1644 , Detachment Ei , Detachment Tama , The Nanking Detachment , or simply Unit Ei , was a Japanese laboratory and biological warfare facility under control of the Epidemic Prevention and Water Purification Department . It was established in 1939 in Japanese-occupied Nanking as a satellite unit of Unit 731 . It had 12 branches and employed about 1,500 men
Unit 731
Unit 731
Unit Ei 1644