The Beirut Bombing occurred on October 23, 1983. The act was a terrorist attack against the United States Marine Headquarters during the Lebanese Civil War. A yellow Mercedes delivery truck, its engine revving, crashed through several fences, then slammed into the headquarters lobby. Once in the lobby, the smiling driver, a Shiite Muslim suicide bomber, encountered unarmed marines and detonated his truck with 12,000 pounds of TNT, creating the largest non-nuclear explosion ever seen by the FBI. The bomb's force leveled the four-story, cinder-block building, killing nearly 300 people. A few months later, President Ronald Reagan ordered the withdrawal of U.S. troops, who had been stationed in Lebanon to provide stability during the civil war between Muslims and Christians.