Earlier, charges against the sixth detainee were dismissed by the U.S. Defense Department's Convening Authority in Guantanamo Bay, Cuba. The reasons were not made public.

But the Defense Department said in a statement that it still has the option of renewing the charges though the sixth detainee would not be tried with the other five.

Each of the five could face the death penalty.

The Convening Authority in Guantanamo, Judge Susan Crawford, "has referred to trial charges against Khalid Sheikh Mohammed, Walid Muhammad Salih Mubarak Bin 'Attash, Ramzi Binalshibh, Ali Abdul Aziz Ali, and Mustafa Ahmed Adam al Hawsawi," the department said. "The five accused will be tried jointly, and the cases are referred as capital for each defendant, meaning they face the possibility of being sentenced to death."

The five are accused of operating training camps, operating a cell in Germany or transferring money to further the Sept. 11 plot in which nearly 3,000 people were killed in the World Trade Center in New York and the Pentagon near Washington when hijacked airliners were flown into them. Khalid Sheikh Mohammed is accused of being the mastermind behind the plot.

The sixth defendant is Mohammed al-Qahtani, detained in 2001 in Florida. Officials say he is suspected of being the failed 20th hijackacker in the plot. Nineteen hijackers died in the airliners.