WINDHAM — An Auburn man is charged with sexually assaulting a female inmate at the Maine Correctional Center in Windham while he was a guard there.

The Portland Press Herald reports that 23-year-old Bret Butterfield is being held at the York County Jail in Alfred on $50,000 cash bail.

Butterfield is accused of assaulting a 25-year-old convicted burglar who was released in April. She is not being identified because she’s considered a victim.

Scott Fish, spokesman for the Department of Corrections, said Butterfield, who began working as a guard at the correctional center in 2012, resigned from his job June 30, but declined to provide any details about the case.

It wasn’t immediately clear if Butterfield had an attorney. He faces up to 10 years in prison if convicted.