40 years since outbreak of Lebanon civil war

Lebanon on Monday commemorated 40 years since the start of its devastating civil war, which left more than 150,000 dead and hundreds of thousands of people displaced.

Following is a list of key events since the start of the conflict.

1975

April 13: Clashes, viewed as the start of Lebanon's 15-year-long civil war, erupt in Beirut between Christians and Palestinians.

1976

June: Syrian troops enter Lebanon to restore peace but also to curb the Palestinians.

October: After Arab summits in Riyadh and Cairo, a ceasefire is arranged and a predominantly Syrian Arab Deterrent Force established to maintain it.

1978

March 14: Israel launches major invasion of Lebanon, in reprisal for a Palestinian attack into its territory.

March 19: UN Security Council passes Resolution 425 calling on Israel to withdraw from all Lebanese territory, and establishing the United Nations Interim Force in Lebanon (UNIFIL) to confirm the withdrawal.

June 13: Israel hands over territory in southern Lebanon to its proxy, the mainly Christian South Lebanon Army (SLA), ignoring UNIFIL.

1982

June 6: After attempted assassination of the Israeli ambassador to Britain, Israel launches full-scale invasion of Lebanon.

September 15: Israeli troops occupy mainly Muslim west Beirut.
September 16-18: Phalangist militia slaughter Palestinians in Sabra and Shatila refugee camps in west Beirut, under eyes of Israeli forces.

September 24: First US, French and Italian peacekeeping forces arrive in Beirut.

1983

May 17: Israel and Lebanon sign accord on Israeli withdrawal, establishing a security zone in southern Lebanon.

October 23: Suicide bombers blow up US peacekeepers' headquarters, killing 241 marines, and destroy a French post, killing 56 troops.

1985

June: Most Israeli troops withdraw but some remain to support its SLA proxy force, led by Antoine Lahad.

1986

Lebanon officially cancels May 1983 agreement with Israel.

1988

September: Lebanon has two governments -- one mainly Muslim in west Beirut, and one Christian, in east Beirut led by Maronite General Michel Aoun.

1989

March 14:  Aoun declares a "war of liberation" against the Syrian presence.
October: Lebanese national assembly, meeting in Taif, Saudi Arabia, endorses a Charter of National Reconciliation, which leads to the end of the civil war. Taif agreement calls for a Syrian pullback to the eastern Bekaa Valley, but does not set a date for a full withdrawal.

1990

October 13: Syrian air force attacks presidential palace and Aoun takes refuge in French embassy, an event regarded as marking the end of the civil war.