0845 NY time / Eastern Daylight time (1245 GMT - all times approximate)

Aircraft strikes the North Tower of World Trade Centre in New York’s financial district causing massive explosion. The American Airlines Boeing 767, flight 11, was hijacked after takeoff from Boston en route to Los Angeles with 81 passengers and 11 crew members on board.

0903
Around 18 minutes later, a second airplane strikes South Tower of World Trade Centre. The United Airlines Boeing 767 flight 175, was also hijacked from Boston en route to Los Angeles with 56 passengers and nine crew on board.

0920
FBI announce further possible hijackings from regional airports.

0930

George Bush, US president, declares: "We have a national tragedy". Vows an all-out hunt for the perpetrators of "an apparent terrorist attack."

0940
Third plane hits Pentagon in Washington, with part of the building collapsing later. The American Airlines Boeing 757, flight 77, hijacked from Dulles Airport in Virginia, also bound for Los Angeles, had 58 passengers and six crew on board. White House and Pentagon evacuated.

0943
Abu Dhabi television reports receiving a phone call from the Democratic Front for the Liberation of Palestine claiming responsibility for the attacks on the World Trade Centre. Reports are later denied by DFLP.

0950
All Airports across the US shut down.
New York Stock Exchange is shut indefinitely.

1000
South Tower of New York World Trade Centre collapses.

1005
United Airlines 93, Boeing 757 from Newark, New Jersey, bound for San Francisco, with 38 passengers and seven crew on board crashes south-east of Pittsburgh in Western Pennsylvania.

1012
Tony Blair, UK prime minister, cancels key speech at TUC to return to London for emergency talks by Cabinet's emergency committee - Cobra. He describes the attacks "the most terrible shocking event."

1035
New York - Second tower collapses.
In the UK, Canary Wharf evacuated.

1104
United Nations Headquarters in New York evacuated.

1118
American Airlines confirm 2 aircraft lost.

1157
Taliban holds press conference, denying Bin Laden responsibility.

1159
United Airlines confirms 1 aircraft lost, believed to be the plane in Pittsburgh.

1248
Hamas, Islamic militant group, denies any connection to attacks.

1337
President Bush arrives in Barksdale Air Force Base, Louisiana from Florida.

1500
President Bush lands at the home of the Strategic Air Command at Offutt Air Force base in Nebraska.

1530
President Bush departs for Washington DC.

1730
Salomon Smith Barney's 47 storey building collapses.