NEW YORK - SEPTEMBER 11, 2001: (PUERTO RICO OUT) (SEPTEMBER 11 RETROSPECTIVE) People run away as the North Tower of World Trade Center collapses after a hijacked airliner hit the building September 11, 2001 in New York City. (Photo by Jose Jimenez/Primera Hora/Getty Images)
394261 50: Civilians flee as a tower of the World Trade Center collapses September 11, 2001 after two airplanes slammed into the twin towers in an alleged terrorist attack. (Photo by Mario Tama/Getty Images)
NEW YORK - SEPTEMBER 11: An unidentified New York City firefighter walks away from Ground Zero after the collapse of the Twin Towers September 11, 2001 in New York City. The World Trade Center's Twin Towers and the Pentagon were attacked by terrorists using commercial airliners as missiles. (Photo by Anthony Correia/Getty Images)
394558 06: A New York City fireman calls for 10 more rescue workers to make their way into the rubble of the World Trade Center September 14, 2001 days after the September 11, 2001 terrorist attack. (U.S. Navy Photo by Jim Watson/Getty Images)
Smoke rises over the New York Skyline from the scene of the World Trade Center Attack, as seen from a tugboat evacuating people from Manhattan to New Jersey. (Photo by Hiro Oshima/WireImage)
