A former Darby Township police officer was charged Thursday with the sexual assault of three women while he was on duty, the Delaware County District Attorney's Office announced.

Kevin Joseph Walker, 43, of Chester, has been charged with rape, sexual assault, aggravated indecent assault, stalking, and related crimes. He was being held in Delaware County prison after failing to post bail, according to public records.

According to court records, in 2010 Walker allegedly performed oral sex on a woman who was in custody. Also in 2010, a second woman, who was pregnant, told investigators that Walker sexually assaulted her at the police station after she was stopped by police and taken there. She was never charged with a crime. The third woman told investigators that in 2009, Walker intimidated her into coming to the police station five or six times, where he forced her to have sex with him. - Mari A. Schaefer