Unit Ei 1644  was established in 1939 in Japanese-occupied Nanking as a satellite unit of Unit 731,  a covert biological and chemical warfare research and development unit of  what army?
Unit Ei 1644 Unit Ei 1644 (Japanese: 栄1644部隊 ) — also known as Unit 1644 — was a laboratory and one of the water purification centers established 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.
Wang Jingjiu Wang Jingjiu or Wang Ching-chiu (王敬久) (1902–1968) was a general in China's National Revolutionary Army. He commanded the 87th Division and was engaged in the Chinese Civil War and suppressing the Chahar People's Anti-Japanese Army in 1933. His Division became one of the Chinese-German trained Divisions forme in 1936-37. It fought under the 71st Corps at the Battle of Shanghai and Battle of Nanking. The following year he commanded 25th Corps in the Battle of Wuhan and in the Battle of Nanchang in 1939. He later commanded the 10th Army Group in the Battle of Zhejiang-Jiangxi of 1942, Western Hubei Campaign of 1943, and Western Hunan Campaign of 1945.