PLO attacks from Lebanon into Israel in 1977 and 1978 escalated tensions between the countries. On 11 March 1978, eleven Fatah fighters landed on a beach in northern Israel and hijacked two buses full of passengers on the Haifa – Tel-Aviv road, shooting at passing vehicles in what became known as the Coastal Road massacre. They killed 37 and wounded 76 Israelis before being killed in a firefight with Israeli forces. Israel invaded Lebanon four days later in Operation Litani. The Israeli Army occupied most of the area south of the Litani River. The UN Security Council passed Resolution 425 calling for immediate Israeli withdrawal and creating the UN Interim Force in Lebanon (UNIFIL), charged with attempting to establish peace.