A man who was held in Guantanamo Bay for two decades after the U.S. accused him of attempting to join the hijackers who carried out the September 11 terror attacks has been sent home to Saudi Arabia. Mohammad Ahmad al-Qahtani, 46, has been held at the U.S. base in Cuba since 2002 after he was accused of being trained by al Qaeda and then unsuccessfully trying to enter the U.S. on Aug. 4, 2001, to take part in attacks. On Monday, he was flown back to Saudi Arabia, where he will receive treatment at a psychiatric facility. Ramzi Kassem, a law professor at the City University of New York who represented al-Qahtani, said: “After two decades without trial in U.S. custody, Mohammed will now receive the psychiatric care he has long needed in Saudi Arabia, with the support of his family.” There are now 38 prisoners left at Guantanamo Bay.