Late summer 1963 saw sporadic incidents attributed to the FFS, but more serious fighting broke out a year later, and the army moved quickly and in force to crush a rebellion. Minister of Defense Boumédiène had no qualms about sending the army to put down regional uprisings because he felt they posed a threat to the state. However, President Ben Bella attempted to co-opt allies from among these regional leaders in order to undermine the ability of military commanders to influence foreign and security policy. Tensions consequently built between Boumédiène and Ben Bella, and in 1965 the military removed Ben Bella in a coup d'état, replacing him with Boumédiène as head of state.