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. But, 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.