The Popular Front Incident (人民戦線事件, Jinmin sensen jiken) refers to the Imperial Japanese government's suppression of a perceived threat from the political left after the fall of Nanjing during the Shōwa period. During the incident, approximately 400 people were arrested by the authorities between December 1937 and February 1938. Amongst those arrested during the incident were Kanson Arahata, Hitoshi Yamakawa, and Ryokichi Minobe.
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Popular Front Incident Wikipedia(Text) CC BY-SA