After the surrender of Japan , the Soviet Red Army discovered secret installations for experimenting with and producing chemical weapons and biological weapons of mass destruction centered around secret Army Unit 731 and its subsidiaries . At these locations , the Kwantung Army was also responsible for some of the most infamous Japanese war crimes , including the operation of several human experimentation programs using live Chinese , American and Russian civilians , and POWs , directed by Dr. Shiro Ishii
Unit 731
Unit 731
Kwantung Army