text: The exodus to mainland France accelerated after the Oran massacre of 1962, in which hundreds of militants entered European sections of the city, and began attacking civilians.Algeria's first president was the Front de Libération Nationale (FLN) leader Ahmed Ben Bella.Morocco's claim to portions of western Algeria led to the Sand War in 1963.Ben Bella was overthrown in 1965 by Houari Boumédiène, his former ally and defence minister.Under Ben Bella, the government had become increasingly socialist and authoritarian; Boumédienne continued this trend.However, he relied much more on the army for his support, and reduced the sole legal party to a symbolic role.He collectivised agriculture and launched a massive industrialisation drive.Oil extraction facilities were nationalised.This was especially beneficial to the leadership after the international 1973 oil crisis.Boumédienne's successor, Chadli Bendjedid, introduced some liberal economic reforms.He promoted a policy of Arabisation in Algerian society and public life.Teachers of Arabic, brought in from other Muslim countries, spread conventional Islamic thought in schools and sowed the seeds of a return to Orthodox Islam.The Algerian economy became increasingly dependent on oil, leading to hardship when the price collapsed during the 1980s oil glut.Economic recession caused by the crash in world oil prices resulted in Algerian social unrest during the 1980s; by the end of the decade, Bendjedid introduced a multi-party system.Political parties developed, such as the Islamic Salvation Front (FIS), a broad coalition of Muslim groups.Civil War (1991–2002) and aftermath In December 1991 the Islamic Salvation Front dominated the first of two rounds of legislative elections.Fearing the election of an Islamist government, the authorities intervened on 11 January 1992, cancelling the elections.Bendjedid resigned and a High Council of State was installed to act as the Presidency.