The CIA's prime source in Lebanon was Bashir Gemayel, a member of the Christian Maronite sect. The CIA was blinded by the uprising against the Maronite minority. Israel invaded Lebanon, and, along with the CIA, propped up Gemayel; this got Gemayel's assurance that Americans would be protected in Lebanon. 13 days later he was assassinated. Imad Mughniyah, a Hezbollah assassin, targeted Americans in retaliation for the Israeli invasion, the Sabra and Shatila massacre, and the US Marines of the Multi-National Force for their role in opposing the PLO in Lebanon. On April 18, 1983, a 2,000 lb car bomb exploded in the lobby of the American embassy in Beirut, killing 63 people, including 17 Americans and 7 CIA officers, among whom was Bob Ames, one of the CIA's best Middle East experts. America's fortunes in Lebanon only suffered more as America's poorly directed retaliation for the bombing was interpreted by many as support for the Christian Maronite minority. On October 23, 1983, two bombs were detonated in Beirut, including a 10-ton bomb at a US military barracks that killed 242 people. Both attacks are believed to have been planned by Iran by way of Mughniyah.