In this Sept. 11, 2001 file photo, the south tower starts to collapse as smoke billows from both buildings of the World Trade Center in New York. (Jim Collins/AP File Photo)

All times are eastern.

8 a.m. American Airlines Flight 11, a Boeing 767 with 92 people on board, takes off from Boston’s Logan International Airport for Los Angeles.

8:14 a.m. United Airlines Flight 175, a Boeing 767 with 65 people on board, takes off from Logan for Los Angeles.

8:21 a.m. American Airlines Flight 77, a Boeing 757 with 64 people on board, takes off from Washington Dulles International Airport for Los Angeles.

8:40 a.m. Federal Aviation Administration notifies North American Aerospace Defense Command’s Northeast Air Defense Sector about suspected hijacking of American Flight 11.

8:41 a.m. United Airlines Flight 93, a Boeing 757 with 44 people on board, takes off from Newark International Airport for San Francisco.

8:43 a.m. FAA notifies NORAD about suspected hijacking of United Flight 175.

8:46 a.m. American Flight 11 crashes into north tower of World Trade Center.

9:03 a.m. United Flight 175 crashes into south tower.

9:08 a.m. FAA bans all takeoffs nationwide for flights going to or through its New York Center airspace.

9:21 a.m. All bridges and tunnels into Manhattan are closed.

9:24 a.m. FAA notifies NORAD about suspected hijacking of American Flight 77.

9:26 a.m. FAA bans takeoffs of all civilian aircraft.

9:31 a.m. President Bush, in Florida, calls crashes an “apparent terrorist attack on our country.”

9:40 a.m. American Flight 77 crashes into Pentagon.

9:45 a.m. FAA orders all aircraft to land at nearest airport as soon as practical. More than 4,500 aircraft are in air at the time.

9:48 a.m. U.S. Capitol and White House’s West Wing evacuated.

9:59 a.m. South tower of trade center collapses.

10:07 a.m. (approx.) United Flight 93 crashes in Pennsylvania field.

10:28 a.m. North tower of trade center collapses.

11:00 a.m. New York Mayor Rudolph Giuliani orders evacuation of lower Manhattan.

1:04 p.m. Bush, at Barksdale Air Force base in Louisiana, announces U.S. military on high alert worldwide.

2:51 p.m. Navy dispatches missile destroyers to New York, Washington.

3:07 p.m. Bush arrives at Strategic Command at Offutt Air Force Base in Nebraska.

5:25 p.m. Empty 47-story 7 World Trade Center collapses.

Source: Associated Press