A guard in a jail in Montgomery County, Maryland, admitted to sexually assaulting a transgender inmate in her cell, police say.

Olukunle A. Oyekanmi, a correctional officer at the Montgomery County Correctional Facility in Boyds, near Clarksburg, is accused of attacking the inmate early Tuesday morning.

An investigation showed that Oyekanmi, 41, entered the woman's cell about 6:20 a.m. and sexually assaulted her, police said. Surveillance video showed Oyekanmi was in the inmate's cell at the time of the alleged attack.

During an interview with Montgomery County police department detectives, Oyekanmi admitted to the assault, police said. He was arrested Tuesday evening at his home.

Information on Oyekanmi's lawyer was not available immediately.

Oyekanmi is charged with second-degree sex offense, second-degree assault, sexual contact with an inmate and malfeasance in office. He was released after he posted $20,000 bond.

Sexual assault rates are strikingly high among transgender people. A U.S. Department of Justice program cites data suggesting that 1 in 2 transgender individuals are sexually abused or assaulted at some point in their lives.