The moments of the worst foreign attack on American soil.
Between 7:59 a.m. and 8:42 a.m., four commercial flights take off: two from Boston, one from Washington, D.C., and one from Newark, N.J., all headed for California. After takeoff, all four planes are hijacked by terrorists affiliated with al Qaeda.
Hijackers crash American Airlines Flight 11 into the North Tower of the World Trade Center.
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Hijackers crash United Airlines Flight 175 into the South Tower of the World Trade Center.
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The second plane crash made it apparent that this was a planned attack, not an accident.
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President Bush is about to begin reading a book to elementary school students in Florida when Chief of Staff Andrew Card tells him that a second plane has crashed into the World Trade Center and that “America is under attack.”
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Hijackers crash American Airlines Flight 77 into the Pentagon.
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The Federal Aviation Administration grounds all flights in the United States.
The White House and U.S. Capitol are evacuated.
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The South Tower collapses. For the first time in known history, the White House requests the implementation of continuity of government measures.
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The White House also requests fighter escorts for Air Force One and a fighter combat air patrol over Washington, D.C.
United Airlines Flight 93 crashes in southern Pennsylvania after a struggle onboard between a team of hijackers and the flight’s passengers.
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Al Qaeda members later claimed that the intended target was the United States Capitol Building in Washington, D.C.
The North Tower collapses.
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The collapse of the World Trade Center caused an immense plume of toxic dust throughout lower Manhattan. Tens of thousands of people have reported long-term medical conditions such as respiratory disease or cancer as a result of inhaling the dust.
New York City Mayor Rudy Giuliani orders an evacuation of lower Manhattan.
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The U.S. Coast Guard led an evacuation of more than 500,000 people from lower Manhattan following the World Trade Center attacks.
Hundreds of firefighters from the New York City Fire Department rushed to the World Trade Center to help rescue survivors.
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343 members of the New York City Fire Department died in the 9/11 attacks as they attempted to save people’s lives. Most perished either after entering the buildings following the plane crashes or by being hit by debris outside.
World Trade Center Building 7, a 47-story building adjacent to the Twin Towers, collapses after debris falling from neighboring buildings caused it to catch fire.
The Sept. 11 attacks caused almost 3,000 fatalities and tens of thousands of injuries, as well as long-term health problems for people exposed to dust and debris.
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President Bush addresses the nation from the White House and says, “Today, our fellow citizens, our way of life, our very freedom came under attack in a series of deliberate and deadly terrorist acts.”
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The rubble of the World Trade Center smolders a day after the 9/11 attacks.
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Sources: 9/11 Memorial & Museum, History.com, The 9/11 Commission Report, Final Report on the Collapse of World Trade Center Building 7 by the U.S. Commerce Department National Institute of Standards and Technology.
Produced by: Elissa Curtis and Angela Owens.
Cover photo: Masatomo Kuriya/Corbis/Getty Images.