Sabra and Shatila massacre
Right before the massacre of the two camps, the current President of Lebanon, Bachir Gemayel, is murdered in a bombing attack on the 14 of September 1982. He also was the leader of the Lebanese Phalanges. In reaction, those take control and close the west part of Beirut, including the Sabra and Shatila camps. Their invasion was helped by Israeli forces, who are sent at the pretext of maintaining order in the capital.