A woman was sexually assaulted in the Calgary neighbourhood of Penbrooke Meadows by a stranger who followed her off a bus, say police.

The attack happened on Thursday at 2 p.m.

The woman had boarded the bus at the Marlborough C-Train station.

"It is believed that a man also got on the bus at the same time but he did not interact with the woman," police said in a press release.

The woman got off the bus at a stop near the intersection of 8 Avenue and 58 Street S.E. She was followed and attacked in the 700 block of 58 Street S.E.

"The man approached the woman, forced her against a fence and started sexually touching her. The woman screamed and scratched the man's face, causing him to flee," said police.

Investigators, who are reviewing CCTV footage, are looking for a man described as Indigenous, in his late 20s and between 5'9" and 6' tall. He was wearing a grey sweater, blue jeans, a backwards red baseball cap and silver rimmed glasses.

Police are asking anyone with information to contact them or Crime Stoppers.