Sept. 11, 2001 / 8:46 a.m. Hijackers crash American Airlines Flight 11 into floors 93 through 99 of the World Trade Center's north tower
9:03 a.m. Hijackers crash United Airlines Flight 175 into floors 78 through 84 of the World Trade Center's south tower
9:37 a.m. Hijackers crash American Airlines Flight 77 into the Pentagon's western facade
9:42 a.m. The Federal Aviation Administration grounds all flights over or bound for the continental United States for the first time in U.S. history
9:59 a.m. After burning for 56 minutes, the south tower of the World Trade Center collapses
10:03 a.m. Hijackers crash United Airlines Flight 93 in a field in Shanksville, Pa., to prevent passengers who mounted a counterattack from retaking the airplane. The crash site is approximately 20 minutes' flying time from Washington
10:28 a.m. After burning for 102 minutes, the north tower of the World Trade Center collapses
8:30 p.m. President George W. Bush addresses the nation: "Today our fellow citizens, our way of life, our very freedom came under attack in a series of deliberate and deadly terrorist acts." The death toll will eventually stand at nearly 3,000, including the 19 hijackers
Sept. 12, 2001 Twenty-six hours after the collapse of the north tower, rescuers pull Genelle Guzman out of the wreckage; she is the last survivor to be rescued
Sept. 14, 2001 Bush visits the World Trade Center site. In an impromptu speech from atop a crushed fire engine, he says, "The people who knocked these buildings down will hear all of us soon."
Sept. 15, 2001 Balbir Singh Sodhi, a Sikh, becomes the nation's first post-9/11 victim of a hate crime when he is gunned down in Mesa, Ariz., while pumping gas at a service station. The killer tells police he was lashing out against "Arabs" after watching the Twin Towers collapse on television over and over again. In the 3½ months following the 9/11 attacks, more than 300 federal criminal investigations will be initiated in response to similar hate incidents
Sept. 16, 2001 Bush names Osama bin Laden the prime suspect. Bin Laden issues a statement: "I stress that I have not carried out this act."
Sept. 17, 2001 Chicago Tribune: "Get bin Laden 'Dead or Alive,' Bush Says"
Oct. 5, 2001 Robert Stevens, a photo editor for the Florida-based tabloid the Sun, dies of pulmonary anthrax after inhaling spores from a letter mailed from Trenton, N.J., on Sept. 18. Other letters are believed to have been sent to ABC News, CBS News, NBC News and the New York Post
Oct. 6, 2001 The last federal rescue team leaves Ground Zero; the mission officially shifts to recovery
Oct. 7, 2001 After the Taliban refuses to hand over Osama bin Laden, the U.S. and its allies launch Operation Enduring Freedom. In an address to the American people, Bush says, "On my orders, the United States military has begun strikes against al-Qaeda terrorist-training camps and military installations of the Taliban regime in Afghanistan." In a videotaped message, bin Laden says, "America [is] full of fear ... Thank God for that."