ORANGEVILLE, Ont. - Provincial police say a potential witness has been unable to help them determine what happened to a missing Orangeville, Ont., woman.

Police appealed Wednesday afternoon for the driver of a white van that was in the area where 42-year-old Sonia Varaschin's car was found on Monday to contact them.

Police said Wednesday night that the driver talked with investigators, but did not see anything that could have helped the investigation.

Police say that based on forensic examinations of Varaschin's residence, and the area where her car was found, they believe she is a "victim of foul play."

Ground, air and trail searches of the Orangeville area have failed to find traces of Varaschin.

Her car was found in an alley Monday morning and police say they found what appeared to be blood on the car and at her residence.

Police told a news conference this afternoon that they have no suspects at the moment but will continue the extensive search for the missing woman.

Varaschin did not show up for work Monday, and her family reported her missing.