During the Soviet occupation of neighbouring Afghanistan, the alliance between the United States and Pakistan was greatly strengthened as the US needed Pakistan as a staging area from which to send weapons to the Mujahideens who were fighting the Soviets. Apprehensive of the two-front threat to Pakistan from India and from Soviet-occupied Afghanistan, the United States in 1981 offered a military aid package of over $1.5 billion, which included 40 F-16 fighters, 100 M-48 tanks, nearly 200 artillery guns and over 1,000 TOW anti-tank missiles, which considerably enhanced Pakistan's defence capability. During the course of the war, Pakistan experienced several air intrusions by Afghan/Soviet pilots and claimed to have shot down eight of these aircraft over the years while losing one F-16 from its own fleet.