(On February 21 Dingmao), March 24, 1927, British and American manufacturing in Nanjing massacre "three four".

1927 3, 24, British and American warships shelled Nanjing, which is one of the crimes during the Northern Expedition imperialist interference in China's revolution. Crusader march to the lower reaches of the Yangtze River in
1927, the United States, Britain, France, Italy, Japan and other countries send more troops and the mobilization of warships threaten to go to Nanjing river, they tried to stop the development of the revolution. March 24, Cheng Qian commanding communists National Revolutionary Army to participate in leadership and combat the Sixth Army and the Second Army defeated after hundreds of thousands of the enemy occupied Nanjing. Night, Anglo-American imperialism excuse for expatriates and consulate by the "mob assault ordered the shelling of Nanjing, the Chinese soldiers and civilians killed or wounded more than 2,000 into the housing property damage numerous, causing massive bloodshed.
after the incident, Britain and other countries to continue to the Chinese military surge reverse China proposed Correctional fierce, wanted compensation and unreasonable demands. March 30, 1928, Chiang Kai-shek sent a special envoy to Nanjing and consular dredge to imperialism apologize, reparations, and ordered the arrest shot and killed Li Fuchun, and Lin Boqu to "apology". This event is a signal of the imperialist armed intervention in the Chinese revolution, Chiang Kai-shek to accelerate in collusion with imperialism, betrayed the revolution of the important steps.