Core Viewpoint - The article reveals the atrocities committed by the Japanese Unit 731 during World War II, including human experimentation and the use of biological weapons against Chinese civilians, as disclosed in recently declassified documents by the Russian Federal Security Service [2][3]. Group 1: Historical Context - The declassified documents indicate that the Japanese military, specifically Unit 731, conducted extensive research on various pathogens to develop biological warfare capabilities, targeting both Soviet and Chinese populations [3][4]. - Over 600,000 Japanese soldiers surrendered to the Soviet Red Army during the conflict in Northeast China, leading to investigations into those involved in biological weapon development [2]. Group 2: Human Experimentation - Unit 731 was responsible for numerous inhumane experiments, including the use of live human subjects to test the effects of diseases such as plague, anthrax, and cholera [3][4]. - The documents detail how Japanese forces used artillery shells filled with pathogens to infect hundreds of Chinese individuals, subsequently collecting data on infection rates to assess the effectiveness of the biological agents [3]. Group 3: Military Strategy - The correspondence from Ivan Dolgikh highlights that Japan had completed significant research on biological warfare methods before launching potential attacks against the Soviet Union from Northeast China [4].