TIMELINE OF THE ATTACKS

The first plane, American Airlines Flight 11, hits the North Tower of the World Trade Center in New York City.

The second plane, United Airlines Flight 175, strikes the South Tower of the World Trade Center in New York City.

The third plane, American Airlines Flight 77, hits the southwest side of the Pentagon.

The World Trade Center’s heavily damaged South Tower collapses.

The fourth plane, United Airlines Flight 93, crashes near Shanksville in the Pennsylvania countryside after passengers attempt to overpower the hijackers.

The World Trade Center’s North Tower falls.

THE HUMAN TOLL