20th hijacker

The 20th hijacker is a possible additional terrorist in the September 11 attacks of 2001, who, for whatever reason, was not able to participate. The 20th hijacker, though not present during the actual attacks, is said to have been deeply involved in the preparations. There were many variations of the 9/11 plot, with the number of terrorists fluctuating with available resources and changing circumstances. In the end, there were 19 hijackers: three of the planes were taken over by five members each and the fourth was hijacked by only four people. The latter plane, United Airlines Flight 93, was also less successful in its mission – instead of hitting any of the obvious targets in Washington, D.C., it crashed into a field near Shanksville, Pennsylvania, due to resistance from passengers. Thus, the idea of a 20th hijacker came to be widely discussed.

Ramzi bin al-Shibh allegedly meant to take part in the attacks and may have served as the hijacker-pilot of American Airlines Flight 77, but he was repeatedly denied a visa for entry into the US. His role as one of the four hijacker-pilots was preceded by Hani Hanjour.

Mohammed al-Qahtani, a Saudi Arabian citizen, is often referred to as the 20th hijacker. José Meléndez-Pérez, a U.S. Immigration inspector at Orlando International Airport refused his entry into the U.S. in August 2001. He was later captured in Afghanistan and imprisoned at the U.S. military prison known as Camp X-Ray at Guantanamo Bay, Cuba. In January 2009, Susan J. Crawford asserted that Qahtani's interrogation at Camp X-Ray amounted to torture.

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