PAIGC in Portuguese Guinea. The dismissal caused considerable public indignation in Portugal, and created favorable conditions for a military overthrow of the existing regime, which had lost all public support. On 25 April 1974 a military coup organized by left-wing Portuguese military officers, the Armed Forces Movement (MFA), overthrew the Estado Novo regime in what came to be known as the Carnation Revolution in Lisbon, Portugal. The coup resulted in a period of economic collapse and political instability, but received general support from the public in its aim of ending the Portuguese war effort in Africa. In the ex-colonies, officers suspected of sympathizing with the prior regime, even black officers, such as Captain Marcelino da Mata, were imprisoned and tortured, while African soldiers who had served in native Portuguese Army units were forced to petition for Portuguese citizenship or else face reprisals from their former enemies in Angola, Guinea, or Mozambique. The Carnation Revolution of 25 April 1974 came as a shock to the United States and other Western powers, as most analysts and the Nixon administration had concluded that Portuguese military success on the battlefield would resolve any political divisions within Portugal concerning the conduct of the war in Portuguese Africa, providing the conditions for US investment there. Most concerned was the apartheid government of South Africa, which launched a deep border incursion operation into Angola to attack guerrilla-controlled areas of the country following the coup. Theaters of war Angola On 3 January 1961 Angolan peasants in the region of Baixa de Cassanje, Malanje, boycotted the Cotonang Company's cotton fields where they worked, demanding better working conditions and higher wages. Cotonang, a company owned by European investors, used native African labor to produce an annual cotton crop for export abroad. The uprising, later to become known as the Baixa de Cassanje revolt, was led by two previously unknown Angolans, António Mariano and Kulu-Xingu. During the protests, African workers burned their identification cards and attacked Portuguese traders. The Portuguese Air Force responded to the rebellion by bombing twenty villages in the area, allegedly using napalm in an attack that resulted in some 400 indigenous Angolan deaths.George, Edward, The Cuban Intervention in Angola, 1965–1991, New York: Frank Cass Publishing Co., (2005) p. 9: Some sources state as many as 7,000 Angolans were killed in the air raids. In the Portuguese Overseas Province of Angola, the call for revolution was taken up