Jordanian army attacks Palestinian guerillas in various areas of Jordan after the PFLP’s hijacking on 6 Sept. of three airliners, marking the beginning of the confrontation between Jordanian and Palestinian forces (‘Black September’). The fighting leaves some 2,000 people, mainly Palestinians, dead. Arafat and the PLO are expelled from Jordan and sets up bases in Lebanon; Israeli air aids against South Lebanon begin. On 19-20 Sept. over 200 Syrian tanks and armored units bearing the symbol of the PLA enter Jordan to temporarily back the PLO.