Gunmen Storm U.S. Embassy in Libya (September 11): Armed gunmen storm the American consulate in Benghazi and shoot and kill U.S. ambassador to Libya Christopher Stevens and three other embassy officials. Stevens, a widely praised diplomat who was an advocate for the opposition in Libya, is the first U.S. ambassador to be killed in the line of duty since 1979. The attack coincides with violent protests at the U.S. embassy in Cairo over the release of a YouTube film, Innocence of Muslims, produced in the U.S., that insulted the Prophet Muhammad and criticized Islam. U.S. officials say they believe that given the weapons used-antiaircraft weapons and rocket-propelled grenades-the attack had been orchestrated in advance. In response to the assault, the U.S. sends 50 marines to protect the embassy in Tripoli. (Sept. 14): Libyan authorities arrest four people who are suspects in the U.S. embassy attack in Benghazi. U.S. officials believe the attack may have been planned in advance. President Obama vows to bring those responsible for the attack to justice.