(CNN) -- The jury in the first U.S. war crimes trial since World War II began deliberating Monday at Guantanamo Bay, according to a Pentagon spokesman.
Salim Hamdan, shown in an undated photo, faces a possible life sentence.
Salim Hamdan, who was Osama bin Laden's former driver, faces a maximum life sentence if convicted of conspiracy and aiding terrorism by a panel of six U.S. military officers.
The trial is being held at the Guantanamo Bay detention facility where he is being held.
Prosecutors in closing arguments Monday said Hamdan's support of bin Laden helped the al Qaeda leader carry out terror plots, including the attacks of September 11, The Associated Press reported.
The defense said Hamdan was just a member of bin Laden's motor pool and had no role in planning terror attacks, according to AP.
Hamdan was captured at a roadblock in Afghanistan in November 2001. He pleaded not guilty at the start of the trial.
During the trial, a U.S. soldier who was present when Hamdan was captured originally said Hamdan was driving a car that had SA-7 surface-to-air missiles intended for al Qaeda. But on cross-examination, the soldier, identified only as Maj. Smith, said he could not be sure Hamdan was the driver of one of the three vehicles carrying the missiles.
Pentagon spokesman Jeff Gordon would not predict how long the jury would deliberate.
"A verdict is expected anytime within the next few hours, or days," he said.
The trial is being conducted under the Military Commissions Act, a law passed in 2006 after the Supreme Court ruled against an earlier Bush administration plan for trying Guantanamo Bay detainees under military rules.
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