@geoffjobson That's right. More clear (also the role of US and UN):

"PLO was respecting the ceasefire agreement then in force with Israel and keeping the border between the Jewish state and Lebanon more stable than it had been for over a decade.[29] During that ceasefire, which lasted eight months, the #UN peacekeeping forces in Lebanon #UNIFIL reported that the PLO had launched not a single act of provocation against Israel.

On 6 June 1982, #Israel invaded #Lebanon moving northwards to surround the capital, Beirut.[31] Following an extended siege of the city, the fighting was brought to an end with a U.S.-brokered agreement between the parties on 21 August 1982, which allowed for safe evacuation of the Palestinian fighters from the city under the supervision of Western nations and guaranteed the protection of refugees and the civilian residents of the refugee camps.
By 1 September, the #PLO fighters had been evacuated from #Beirut under the supervision of Multinational Force.
On 11 September 1982, the international forces that were guaranteeing the safety of Palestinian refugees left Beirut."
en.m.wikipedia.org/wiki/Sabra_…
@palestine

the killing of between 460 and 3,500 Christians, mostly Arab Palestinians in Beirut, Lebanon; during the1982 Lebanon War

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