Political map of the Eastern Mediterranean 19 March 1978 (Operation Litani): In March 1978 Palestinians based in southern Lebanon (Palestinian insurgency in South Lebanon) mounted a major terrorist attack on Israel (Coastal Road massacre). In response, Israel invaded Lebanon (1978 South Lebanon conflict), occupying the area south of the Litani River. After several days fighting, the UN intervened (United Nations Security Council Resolution 425), imposing a ceasefire on both sides and establishing a peace-keeping force (UNIFIL) in the country (United Nations Interim Force in Lebanon).