BARRIE, ONT. -- Ontario's watchdog is investigating a woman's death in Springwater Township late Tuesday night and says it has identified the driver and vehicle involved in the hit and run.

The Special Investigations Unit (SIU) said that on the night of the incident, a caller alerted the OPP that a woman was standing on Highway 26 near Carson Road shortly before 11 p.m. with a dog waving her arms.

One minute later, the SIU said the OPP got another call from an off-duty Barrie police officer who was in the area who said that the vehicle in front of his swerved to avoid something lying on the road.

The SIU said an OPP officer was driving that vehicle, and when both officers got out of their cars, they found the woman lying there.

The SIU said officers attempted first aid and Simcoe County Paramedics took the woman to the hospital where she was pronounced dead.

Officers said they also found the body of the dog off the road.

The investigation is ongoing, and police are appealing for witnesses.

There was no word on an arrest or charges at this time.

Anyone with information is asked to contact the lead investigator at 1-800-787-8529.