TORONTO -- Toronto police are asking the public's help in tracking down a suspect in a sexual assault case.

They say a woman was assaulted in a bus shelter in the Pharmacy Avenue and Ellesmere Road area early Thursday afternoon.

They allege the assailant had been on the same transit bus as the woman, got off at the same stop, engaged the woman in conversation, and then assaulted her.

Police describe the suspect as being 30-to-40 years old, with a brown complexion, brown hair and eyes, about five-feet eight inches tall with a heavy build.

He was wearing a white winter coat at the time of the alleged attack.