Sgt. Paul Edwards says a report of a car fire at the Target Industrial Park in Bangor came in just before 4 a.m. Monday.
Responders found three people dead in the vehicle in the parking lot of a business called Automatic Distributors. The company is a wholesaler of parts and equipment for all-terrain vehicles, snowmobiles, off-road motorcycles and other outdoor activities.
Edwards says the car fire was reported by someone heading to work in the park and he calls the deaths suspicious. Police are asking for other witnesses to step forward.
The state Fire Marshal's office has been called to assist in the investigation.
No additional details are immediately available.