On October 23, 1983, Over 241 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 Sabra 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. Muslim 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 massive 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. A second truck struck the Drakkar building where French peacekeepers were located. 58 French peacekeepers were killed in that bombing. Most reports claimed that the Syrians were behind the attack, driven by their desire to force the Americans out of Beirut. That goal was achieved and, on February 26, 1984, when the last American Marines left Beirut.