AP

Majid Khan, seen here in 1999 family photo, moved to Maryland with his family in 1996 and graduated from a suburban Baltimore high school.

Updated at 11:15 a.m. ET: GUANTANAMO BAY NAVAL BASE, Cuba -- A former CIA "ghost prisoner" who grew up in the Baltimore area admitted to a U.S. war crimes court on Wednesday that he was an al-Qaida money courier and martyr-in-training now prepared to help prosecute other terrorism suspects.

A lawyer entered a guilty plea to five charges, including murder, on behalf of Majid Khan at the Guantanamo Bay naval base in Cuba. Asked by the judge if he understood the plea, Khan answered in English, "yes, sir."

Khan was the first of the so-called "high-value" detainees to plead guilty.

A ghost prisoner is an official term for someone whose identity has been hidden and unregistered at a detention center.

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After nearly nine years in U.S. custody, the Pakistani native appeared in public for the first time at the top-security courtroom. He pleaded guilty in a deal that spares him from a potential life sentence in exchange for helping prosecute other prisoners.

He faces up to 25 years in prison but will likely serve far less. Sentencing will be deferred to 2016.

Khan, a square-faced 32-year-old with short black hair, goatee and glasses, wore a dark suit, white shirt and tie as he stood in court next to his military lawyer, Army Lieutenant Colonel Jon Jackson, who spoke on his behalf.

His lawyers were seeking to seal the details of his deal to protect him and his family. Prosecutors said it should be open because of overwhelming public interest. A judge was expected to rule on the issue Wednesday.

Khan moved to Maryland with his family in 1996 and graduated from a suburban Baltimore high school. He met self-described Sept. 11 mastermind Khalid Sheikh Mohammed during a trip to Pakistan in 2002 and became his acolyte.

Images: Life goes on in Guantanamo

Under Mohammed's instruction, Khan passed a test designed to prove his willingness to become an al-Qaida suicide bomber. He donned a fake bomb vest and waited to set it off in a mosque in Karachi where he was told then-Pakistani President Pervez Musharraf would show up.

Khan also delivered $50,000 of al-Qaida cash to the group that drove a truck bomb into the JW Marriott Hotel in Jakarta in 2003, killing eight people and wounding dozens.

A California woman who survived the blast watched Wednesday's hearing from behind a glass wall in the courtroom spectators' gallery.

Khan's parents and other relatives were scheduled to watch via closed-circuit television at a Maryland military base. He also has a wife in Pakistan and a daughter he has never seen.

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Pakistani police arrested Khan at his brother's house in Pakistan in March 2003 and turned him over to the CIA. His family did not learn what had happened to him until three and a half years later, when then-President George W. Bush announced he had closed the secret prisons and sent Khan and more than a dozen other CIA ghost prisoners to Guantanamo.

Khan is the seventh captive convicted in the still-evolving Guantanamo tribunals designed to prosecute non-U.S. citizens on terrorism charges outside the regular civilian and military courts. He is the fifth to plead guilty in exchange for leniency.

Four of those guilty pleas have occurred under the administration of President Barack Obama, whose attempts to close the Guantanamo detention camp and move the trials into civilian federal courts have been thwarted by Congress.

Msnbc.com staff, Reuters and The Associated Press contributed to this report.

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