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Visitors gather near a flag marking the spot where on September 11, 2001 a passenger jet was flown into the Pentagon building, in Washington

Visitors gather near a flag marking the spot where on September 11, 2001 a passenger jet was flown into the Pentagon building, during ceremonies marking the 10th anniversary of the 9/11 attack on the Pentagon, in Washington, September 11, 2011. (REUTERS/Jason Reed)

9/11 Pentagon ceremony

January 1, 1970

Remembering the September 11, 2011 attack on the Pentagon.