Police in York Region are investigating a sexual assault that took place early Wednesday morning as a young woman stepped off a bus.

The 23-year-old woman exited the bus at Yonge Street and Bernard Avenue at about 6:15 a.m. when a male passenger, who had also been on the bus, struck up a conversation.

Police say the woman was touched inappropriately.

The woman managed to break free from the suspect and called police. The suspect was seen running northbound on Yonge where he boarded a Viva bus.

The suspect is described as having a dark complexion with short black hair. He is believed to be in his late twenties, weighing about 150 to 160 lbs.

Police say the suspect spoke with an accent and was wearing a dark-coloured jacket and a backpack at the time the incident occurred.

Anyone with information is being asked to call York Regional Police sex assault bureau at 1-866-876-5423 ext. 7071. Those who wish to leave an anonymous tip can do so by calling Crime Stoppers at 1-800-222-TIPS.