A third man died when he was thrown from the car, leaving the front seat passenger the only survivor.

Investigations into the accident continued yesterday, with police from the Southern Region Crash Investigation Unit interviewing family of the victims and witnesses to the accident.

While the formal identification is still being completed, police say the three men killed are believed to be Adam Nall, 27, from Oak Flats, Roach Bannerman, 19, from Brownsville, and Aaron Sinadinovic, 24, from Farmborough Heights.

A passenger - Daniel Schroeder, 21, of Horsley - was pulled from the burning vehicle by passersby. Mr Nall has been identified as the driver of the eight-year-old HSV Clubsport R8.

Police allege the vehicle was travelling south at "high speed" near Orangegrove Ave when the driver lost control. At that stage it is believed the car mounted the gutter and collided with a chain link fence and telegraph pole simultaneously.

The impact rotated the car, which destroyed three trees, before it collided with a gas main that ignited.

Skid marks start 50m away near the Orangegrove Ave intersection.

Sergeant Martin Pearce said there was no indication the sedan collided with another vehicle or object.

Post-mortems are yet to take place and a report will be prepared for the information of the coroner.

Anyone with information about the incident, or who saw the dark green Commodore in Unanderra before the crash, is urged to contact the Warilla Police Station on 4295 2699 or Crime Stoppers on 1800 333 000.