Israel occupied Southern Lebanon from 1982 until 2000. In June 1982, Israel invaded Lebanon in response to attacks from southern Lebanon by Palestinian militants.1 The Israel Defense Forces (IDF) occupied the southern half of Lebanon as far as the capital city Beirut, together with allied Maronite Christian paramilitaries involved in the Lebanese Civil War. The IDF left Beirut on 29 September 1982, but continued to occupy the country's southern half. Amid rising casualties from guerrilla attacks, the IDF withdrew south to the Awali river on 3 September 1983. From February to April 1985, the IDF carried out a phased withdrawal to a "Security Zone" along the border, which it said was to protect northern Israel. From this point onwards, Israel supported the South Lebanon Army (SLA), the Lebanese Christian paramilitary, against Hezbollah and other Muslim militants. They fought a guerrilla war in Southern Lebanon throughout the occupation. The Security Zone covered about 800 square kilometres (310 sq mi), roughly 10% of Lebanon's land area. It ran the length of the Israel-Lebanon border and reached between 5 kilometres (3.1 mi) to 20 kilometres (12 mi) deep into Lebanon. It was home to about 180,000 people – 6% of Lebanon's population – living in around a hundred villages and small towns. In 1993, it was estimated that there were 1,000–2,000 Israeli troops and 2,300 SLA troops in the zone. While the IDF oversaw the region's general security, the SLA managed most of the occupied territory's affairs, including the operation of the Khiam detention centre. The SLA also controlled an enclave around Jezzine, just north of the Security Zone. Most of Israel's Security Zone lay within the area patrolled by United Nations peacekeepers from the United Nations Interim Force in Lebanon (UNIFIL), who had been deployed there since Israel's 1978 invasion.