Guerrilla movement formed to oppose the Japanese occupation of Malaya (Peninsular Malaysia) during World War II. The British military, foreseeing a Japanese invasion, trained small groups of Malayans as guerrilla troops; these became the MPAJA. Members of the MPAJA, who were primarily Chinese communists, emerged as heroes from the war and attempted to seize power before the British military returned. Its leadership then went underground until 1948, when they initiated the uprising called the Malayan Emergency