 Chiang found out about this plot, which most likely led to his determination to purge the CPC from KMT.In response to the advances of the NRA, Communists in Shanghai began to plan uprisings against the warlord forces controlling the city.On March 21–22 KMT and CPC union workers led by Zhou Enlai and Chen Duxiu launched an armed uprising in Shanghai, defeating the warlord forces of the Zhili clique.