A state deputy sheriff is accused of sexually assaulting a woman last year while she was in custody.

Benjamin Fonoti was indicted by a grand jury Thursday on second-degree and third-degree sexual assault that allegedly occurred on Oct. 10, 2011.

He voluntarily tuned himself in and was booked by the sheriff’s department and released after posting $11,000 bail.

According to the two-page indictment, Fonoti allegedly made the victim perform a sexual act on him while she was in his custody in the cellblock in District Court.

He has been with the state Department of Public Safety since 2009. A department spokeswoman said an internal investigation was initiated after the department learned about the alleged incident. However, agency the would not say whether Fonoti has been placed on unpaid leave.