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On Sept. 11, 2001, hijackers caught U.S. authorities by surprise with a bold attack on New York City's World Trade Center. At 8:46 a.m., American Airlines Flight 11 carrying 92 people, speared into the 110-story north tower. At 9:03 a.m., United Airlines Flight 175, carrying 65 people, crashed into the 84th floor of the south tower.
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People in front of New York's St. Patrick's Cathedral react with horror as they look down Fifth Ave towards the World Trade Center towers after planes crashed into their upper floors.
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President Bush is interrupted at 9:07 a.m. during a school visit in Sarasota, Florida., by Andrew Card, his chief of staff, and infromed that a second plane has hit the World Trade Center. Bush leaves the school session and sets off on a secretive hopscotch flight aboard Air Force One, stopping at an Air Force Base in Louisiana and NORAD headquarters in Nebraska before returning to the White House in late afternoon. "Thousands of lives were suddenly ended by evil, despicable acts of terror," Bush told the nation during a late-night television address.
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A fiery blasts rocks the World Trade Center.
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Smoke comes out from the Southwest E-ring of the Pentagon building in Arlington, Virginia after a plane crashed into the building and set off a huge explosion.
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A person jumps from the north tower of New York's World Trade Center as another clings to the outside while smoke and fire billow from the building.
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Two women hold each other as they watch the World Trade Center burn.
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Smoke and debris fill the air in New York City as the south tower of the World Trade Center collapses at 9:59 a.m. "Clearly, not even the police and FBI who had flooded the area were worried about collapse," said George Hackett of Newsweek. "They wouldn't have been anywhere near to the buildings as they were. If the first building hadn't essentially fallen straight down, its crash could have killed hundreds standing, like me, a few blocks away."
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Smoke and debris fill the streets as pedestrians run for cover after the collapse of the south tower. What started as a bright sunny day turned to darkness. "Suddenly the top of [the tower] just shattered into tens of thousands of pieces," said Steve Johnson of msnbc.com. "You could see the whole thing just disappeared. Then the smoke came up. The cops started yelling, 'Get back! Run! Get Away!' I ran inside a hotel, and it went black outside because of the dust."
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A woman covered in dust takes refuge in an office building after the top of one of the World Trade Center towers collapsed. The woman was caught outside on the street as the cloud of smoke and dust enveloped the area.
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A woman reacts to a third explosion, possibly the collapse of the World Trade Center towers, while observing from the Brooklyn Promenade, which provides a view of the Manhattan skyline, Sept. 11, 2001, in New York.
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People cross the Brooklyn Bridge to escape the carnage in lower Manhattan. "What was most amazing was how calm people were," said msnbc.com's Michelle Prell. "Maybe everyone was just in shock. But the mass of the city, this huge population, had to get out of the city, and they seemed to be doing it very matter of factly."
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People walk in the street where the World Trade Center buildings collapsed.
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Rescue workers move the body of the Rev. Mychal Judge, 68, away from the base of the north tower. Judge, the New York Fire Department chaplain, died in the line of duty when struck by debris from the south tower while administering last rites to a firefighter. At 10:28 a.m. the trade center's north tower collapsed and debris flattened the adjacent 5 World Trade Center building and buried the NYFD command post on West Street, killing many senior officials.
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FBI investigators comb the crater left by the crash of United Airlines flight 93, a Boeing 757 in Shanksville, Pennsylvania on Wednesday, Sept. 12, 2001. The plane crashed about 80 miles southeast of Pittsburgh after first flying near Cleveland and then turning around. The plane was said to be flying erratically and losing altitude. FBI assistant agent in charge Roland Corvington said that more than 200 investigators were on the scene.
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A man stands in the rubble and calls out asking if anyone needs help, after the collapse of the first World Trade Center Tower.
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Delayed Southwest flights are seen on a television monitor at the Oakland International Airport on Sept. 11, 2001. All flights in the country regulated by the FAA were cancelled after attacks in New York and Washington.
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A firefighter pauses during a search through the rubble of the World Trade Center.
THOMAS E. FRANKLIN / AP
Firefighters raise a flag at the World Trade Center as work at the site continues after hijackers crashed two airliners into the center.
New Yorkers stand motionless and silent on board the first Staten Island ferry to approach Manhattan after the World Trade Center attack.
FULL COVERAGE: Remembering 9/11
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