In pictures: Crash chronology

The space shuttle Columbia had been returning from a 16-day mission when it lost contact with controllers.

Nasa said the shuttle was about 200,000 feet up and travelling at 12,500 mph (20,000 km/h) at the time.

Click here for pictures of the astronauts' final mission

Initially, the shuttle's re-entry over Texas appeared to be going to plan

However, the plume following the shuttle soon thickened, indicating there was trouble

As pieces began to fall from Columbia, explosions of light could be seen from the ground

Debris from Columbia soon began landing over a wide area of Texas, including just outside Rice High School in Texas

People pay their respects at the site of fallen debris found in Nacogdoches, Texas