Firefighters have discovered a body in a burnt out car in Melbourne's south-east, after putting out a fire that police have described as a "shocking crime".

Fire crews were called to a reserve on Frawley Road at Eumemmerring at 11:46pm when a couple of neighbours saw the car on fire and heard an explosion.

Detective Inspector Stuart Bailey said they found the unidentified body after the blaze in the red Commodore was put out.

"Forensically, it indicates we're dealing with a homicide here," he said.

"It is a shocking crime and it would have been extremely distressing for the CFA members getting here late last night to extinguish the fire and find the deceased male in the car."

The car was found just a short distance from a children's playground.

Although the engine and boot of the car were not damaged, Detective Inspector Bailey said police would probably have to rely on dental records and DNA to identify the victim.

He said it was unclear when the person died, whether before or after the fire.

"The owner of the car is a 40-year-old Asian man. He is known to police and has a history of drug involvement," Detective Inspector Bailey said.

"The owner of that car is yet to be seen. We are not sure at this point in time whether the owner of the car is the deceased person."

Detective Inspector Bailey said some passers-by were able to provide details about what happened.

"Those details were there was a car that drove in here, which was a white hatch," he said.

"We've identified that hatch and the person. They just saw the car on fire and drove into the area.

"We're currently getting a statement from that person."