June 1, 2011
US military prosecutors have filed new charges against self-described 9/11 mastermind Khalid Sheikh Mohammed and four alleged co-conspirators, held at Guantanamo Bay.
The charges of murder and conspiracy could result in the death penalty.
Five defendants had previously been charged at Guantanamo over the attacks.
But the charges were set aside as the Obama administration tried to move the trial into US civilian courts; a move which was reversed in April.