City police are investigating a sexual assault after a woman was accosted by a naked man in a northwest cemetery over the weekend.

Police say at around 1 p.m. Saturday, a woman was in the north end of Queen’s Park Cemetery near a creek when she was grabbed from behind by a nude man and pushed to the ground.

The man forced himself on her and told her to take off her clothes. When the woman fought back, the man got up and walked toward the trees, police said.

The attacker is described as Caucasian, in his late 40s, about five foot seven and 140 pounds, with brown, chin-length hair, protruding lips and is possibly toothless.

Anyone who has information on the incident or recognizes the man in the police sketch is urged to contact police or CrimeStoppers.