9/11 'Mastermind' Khalid Sheikh Muhammad Appears At U.S. Tribunal

The self-styled mastermind of the 9/11 attacks in the United States that killed nearly 3,000 people has appeared wearing camouflage at his Guantanamo military tribunal.

Khalid Sheikh Muhammad wore a camouflage vest over a white tunic as he sat at his defense table in a heavily guarded courtroom on the U.S. base in Cuba on October 17.

A long-serving lieutenant to Al-Qaeda leader Osama bin Laden, Muhammad and one other defendant attended the pretrial motions hearing.

Three defendants chose to stay in their cells.

The five are charged with planning and aiding the worst terrorist attack ever on U.S. soil on September 11, 2001, when three passenger airplanes were hijacked and slammed into the World Trade Center in New York and the Pentagon.

A fourth jet crashing after passengers tried to retake it from the hijackers before it could be aimed at the U.S. Capitol Building.

Based on reporting by AP and AFP