Fort Bliss, Texas ? A man once considered a top al-Qaida operative escaped from a U.S.-run detention facility in Afghanistan and cannot testify against the soldier who allegedly mistreated him, a defense lawyer involved in a prison abuse case said Tuesday.

Omar al-Farouq was one of Osama bin Laden’s top lieutenants in Southeast Asia until Indonesian authorities captured him in the summer of 2002 and turned him over to the United States.

A Pentagon official in Washington confirmed Tuesday evening that al-Farouq escaped from a U.S. detention facility in Bagram, Afghanistan, on July 10. The official spoke on condition of anonymity because of the sensitivity of the information.

An Army lawyer for Sgt. Alan J. Driver, a reservist accused of abusing Bagram detainees, asked Tuesday where al-Farouq was and what the Army had done to find him in time for Driver’s court proceedings.

Capt. John B. Parker, a prosecutor, said al-Farouq and three others escaped from the Bagram detention center and have not been found.

Driver, a reservist from the Ohio-based 377th Military Police Company, is charged with maltreatment and assault of three detainees, including one who later died, at the Bagram facility in 2002. He is accused of slamming al-Farouq against a wall.