Investigators are hoping a key witness will come forward after a woman was sexually assaulted at the University of Victoria over the weekend.

Saanich Police say the woman was sexually assaulted in a wooded area across from a parking lot, near several student residences, sometime between midnight and 1 a.m. Saturday.

Police initially said up to five men may have been involved in the assault, but now say they can't confirm how many people were involved.

Details of the attack remain unclear, and police say they’re still looking to talk to at least one more witness who may have stepped in to help the woman.

“It would appear that this individual may have intervened on the attack on the female student, and prevented the incident from proceeding further,” Sgt. Steve Eassie said in a news release. “We also believe that this person may have information that may assist us with our ongoing investigation.”

No arrests have been made and police have not released a description of the suspect or suspects involved.

UVic posted a safety bulleting on its website about the attack, and said campus patrol will be “closely montoring” the area where the assault took place.

Anyone with information is asked to call Saanich Police at 250-475-4321 or Crime Stoppers at 1-800-222-8477.