NEW YORK -- Five men accused of helping plot the Sept. 11 attacks will face trial by military commission later this year, Defense Department officials said Tuesday. Among those to be tried, Khalid Sheikh Mohammed, one of the key masterminds of the attacks, officials said.

The trial will take place in Guantanamo Bay, Cuba and the terror suspects are charged with 169 overt acts that led to the deaths of 2,973 people, the Defense Department said in a statement. The five suspects will be tried together.

Mohammed is accused of being the leader of the attacks. Investigators said he first proposed the plan to Osama Bin Laden back in 1996. Officials said Mohammed personally supervised the operation, including getting funds from Bin Laden and helping to train the hijackers at camps in Afghanistan.

Ramzi Binalshibh allegedly lived with the hijackers in Hamburg, Germany and officials said he made a “martyr video” in advance of the attacks. But he was unable to get a U.S. visa. Instead, Binalshibh is accused of helping the hijackers get training in flight schools as well as providing financial support to the terrorists.

Officials said Walid Muhammad Bin Attash ran a terror training camp in Afghanistan where two of the Sept. 11 hijackers allegedly trained. Bin Attash is also accused of traveling to Malaysia in 1999 to scout security measures at airports by U.S. airliners.

Ali Abdul Aziz Ali allegedly sent more than $120,000 to the hijackers to help pay for their flight training and other expenses. Officials said he also helped the hijackers travel to the U.S. as part of the terror conspiracy.

Mustafa Ahmed al Hawsawi is accused of providing money and clothing to the terrorists including allegedly transferring thousands of dollars overseas to help the plotters.

If convicted, the five suspects could face the death penalty.

Jonathan Hafetz, of NYU's Brennan Center, has been a critic of the treatment of prisoners at Guantanamo.

"The administration has still failed to make the case why any suspected terrorist at Guantanamo can't be brought to justice through a criminal trial in federal court," he said. "Seven years after Guantanamo opened, there are still no convictions and no fair process."

Charges against a sixth suspect, Mohamed Al Khatani, were dismissed. But now he will likely be charged and tried separately, Defense Department officials said. Hafetz said Khatani's admissions were the result of extreme interrogation techniques and the decision to eventually try him separately from the others highlights the troubles with the way detainees have been treated.

The Defense Department said under the military commissions, the suspects can elect not to testify, be represented by military counsel, to examine all evidence and to cross-examine all prosecution witnesses.

A military spokesman said the suspects will be arraigned on the charges in the next 30 days. The trial could start within four to five months depending in part of defense motions.