MARTIN COUNTY, Fla. (CBS12) — What first appeared to be a crash became a death investigation after deputies found charred human remains inside a burning truck.

Deputies with the Martin County Sheriff’s Office and Fire Department reportedly responded to a fully engulfed truck fire just after 9 p.m. on Saturday.

The truck was located off the side of the road near Citrus Blvd. and Pineapple Court, per MCSO.

Inside the truck, deputies made a grizzly discovery. In the passenger seat was the driver’s charred remains, burned beyond recognition.

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While the fire was originally believed to be caused by a traffic accident, that was later ruled out, and detectives were called to the scene.

The investigation revealed the fire was likely caused by the truck’s exhaust igniting grass beneath the vehicle.

For reasons that are unknown to investigators, the driver was unable to escape.

Detectives say they believe they have identified the victim and have been in contact with his family.

However, because of the condition of the body, authorities cannot make an identification until DNA testing is completed, a process that could take several weeks.