The convicted ringleader of detainee abuses at Abu Ghraib was released Saturday from a military prison, an Army spokeswoman said.

Charles Graner Jr., 42, was released from the U.S. Disciplinary Barracks at Fort Leavenworth, Kan., around 10 a.m. Saturday after serving more than 6½ years of a 10-year sentence, spokeswoman Rebecca Steed said. Graner will be under the supervision of a probation officer until Dec. 25, 2014, she said.

Steed said she could not release any information about Graner’s whereabouts or his destination after release. Neither Graner nor his wife — who was a fellow Abu Ghraib defendant — have responded to interview requests.

Graner was an Army Reserve corporal from Uniontown, Pa., when he and six other members of the Maryland-based 372nd Military Police Company were charged in 2004 with abusing detainees at the prison in Iraq.