Over 200 marines were killed when a truck loaded with explosives crashed into the US Marine compound at Beirut Airport. The Marines, who had been in Beirut as part of a multi-national force to promote peace in Lebanon, soon withdrew.
The United States initially committed 800 Marines as part of a multi-national force to oversee the evacuation of the PLO from Beirut. This took place on August 23, 1982. The Marines stayed in Beirut for only a short while, withdrawing on September 10. Fifteen days later, the Lebanese President elect, Bashir Gemayel, was assassinated. In the resulting chaos, Israeli forces moved into West Beirut, and Christians murdered approximately 400 Palestinians at the Shatila and Sabre refugee camps. As a result, American Marines were recommitted to Beirut.
In the succeeding weeks and months, the Americans began to ally themselves with the government of Lebanon. Moslem fundamentalists, with the support of Syria, began to actively harass American forces, engaging them with sniper fire and occasional artillery fire. On April 18, a large bomb went off at the American embassy in Beirut, killing 61 people, including 17 Americans.
As the Israelis withdrew from much of Lebanon, the inter- Lebanese attacks, as well as the attacks against American forces, worsened.
On October 23, a suicide truck containing 12,000 pounds of explosives was driven into the American Marine compound at the Beirut Airport, killing 241 Marines. Most reports claimed that the Syrians were behind the bombing, driven by their desire to force the Americans out of Beirut. Thar goal was achieved and, on February 26, 1984, the last American Marines left Beirut.