The Shanghai massacre of 1927 and the Night of the Long Knives of 1934, in which the leader of a political party turned against and killed a particular section or group within the party, are commonly called "purges" while mass expulsions on grounds of racism and xenophobia, such as that of the Crimean Tatars and the Japanese-American internment are not.
Though sudden and violent purges are notable, most purges do not involve immediate execution or imprisonment, for example the periodic massive purges of the Communist Party of Czechoslovakia on grounds of apathy or dereliction, or the purge of Jews and political dissenters from the German Civil Service in 1933–1934. Mao Zedong and his associates purged much of the Chinese Communist Party's leadership, including the head of state, President Liu Shaoqi and the then-General Secretary, Deng Xiaoping, beginning in 1966 as part of the Cultural Revolution. In Maoist states, sentences usually involved hard labor in laogai camps and executions. Deng Xiaoping acquired a reputation for returning to power after having been purged several times.