Chris Parvi, a member of the Naval Air Station Whidbey Island Fire Department, tolls a bell in memory of firefighters who lost their lives in the 9/11 attacks as he participates in a ceremony commemorating the 13th anniversary of 9/11, Sept. 11, 2014, in Oak Harbor, Wash. Terrorists hijacked four passenger aircraft Sept. 11, 2001. Two of the aircraft were deliberately crashed into the World Trade Center in New York; one was crashed into the Pentagon; the fourth crashed near Shanksville, Pa. Nearly 3,000 people died in the attacks. (U.S. Navy photo by Mass Communication Specialist 2nd Class John Hetherington/Released)