The self-proclaimed 9/11 mastermind and his four terrorist cohorts will move closer Saturday to their long-awaited trial when the men are arraigned at a Guantanamo Bay military commission.

Khalid Sheik Mohammed and the others are accused of planning and orchestrating the Sept. 11, 2001, attacks in which Al Qaeda operatives hijacked four U.S. commercial jets, slamming two into the World Trade Center towers and one into the Pentagon, killing nearly 3,000 people. The fourth plane in the attack was retaken by passengers and crashed in an empty field in Shanksville, Pa., killing all on board.

The arraignment follows the conviction Tuesday of a Bosnian-born U.S. citizen for his role in a suicide-bomb plot on New York City subways. Adis Medunjanin now faces life in prison for planning the attack with two high school classmates, timed for the eighth anniversary of the Sept. 11 attacks. They received Al Qaeda training in Pakistan before agreeing to strap on backpack bombs on the subway, prosecutors said at the trial.

The trial of the Guantanamo five is expected to begin in the next several months. They face charges that include murder and terrorism and could be put to death if convicted. The arraignment this weekend follows the one-year anniversary of Al Qaeda leader Usama bin Laden's death. 

The lawyers for defendant Mustafa al-Hawsawi have recently filed a motion stating the military court lacks authority to proceed with the trial because of "critical omissions" during the recent death-penalty authorization period. 

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The other defendants have joined in the motion, as lawyers claim their efforts to build a defense were thwarted by "deliberate and systematic interference with attorney client communications." 

Defense lawyers also say they have not had access to classified evidence and such essential resources such as cleared personnel, Arabic translators and investigators. "The odds continue to be silently and deliberately stacked against a fair process,” said Cmdr. Walter Ruiz, a military lawyer representing Hawsawi.

The judge, Army Col. James Pohl, has established eight viewing sites at military bases in the eastern United States where the proceedings will be broadcast on closed-circuit TV.

Five sites will be for 9/11 rescuers, survivors and their families -- Fort Meade in Maryland; Fort Hamilton and another site to be announced in New York City; Joint Base McGuire Dix in Lakehurst, N.J.; and Fort Devens in Massachusetts.

Two additional sites at Fort Meade and one in Washington, D.C., will be for the public, journalists and government officials to watch.

Fort Meade began showing closed-circuit TV coverage last year of preliminary proceedings from the military base at Guantanamo Bay, Cuba but has yet to broadcast tribunal proceedings so widely.

Pohl also presided at the trials of nine soldiers found guilty of abusing detainees at the Abu Ghraib prison in Iraq.

This is the second time the U.S. has tried to prosecute the Guantanamo prisoners.

The Obama administration initially tried to move the case from a military commission to a civilian court in the U.S. as part of an effort to close the Cuba prison. But the administration was forced to reverse course because of opposition in Congress and by New York City officials who said the case posed too great of a security threat.

Lawyers for some defendants called for a wider audience.

"We want it more transparent and more open," said Cheryl Bormann, a lawyer for defendant Waleed bin Attash. "We believe that the world needs to see what's happening."

The Associated Press contributed to this report.