The 71-year-old Wanniassa man died at the scene of the single vehicle accident on Wednesday, September 10.  

A post-mortem examination is being conducted but police believe the man suffered a medical episode prior to the crash.

Queanbeyan Police officers performed CPR and attempted to revive the man for 30 mins but he was unresponsive. 

"At this stage, the cause of death is unknown. We are yet to determine whether the accident was the cause of death or if the driver had an existing medical condition, which may have also caused the accident," Queanbeyan Inspector Chris Varley said.

The accident occurred sometime after 11.30am and police described the car, a grey Ford Falcon utility as "ping ponging" across the road.

"The driver has veered to the left side of the road and clipped a power pole. The car has come back and hit a guardrail, travelled across the media strip and hit another guard rail.

"The car appeared to bounce or 'ping pong', back and forth across the road. It's quite a wide road so that may indicate there was something medically wrong," Insp. Varley said.

The stretch of Lanyon Drive between the Canberra Avenue and Southbar Road roundabouts was closed for several hours as officers carried out their investigations.

Specialist crash police from Goulburn travelled down to assess the scene and prepare a report for the coroner.

The crash was the first of two fatalities in the region in a matter of hours.

A woman was killed after she was struck by a QCity bus carrying school children while crossing Canberra Avenue in Griffith at about 3.55pm.

Police have asked anyone who many have witnessed either of the collisions and has not yet spoken to police, to contact CrimeStoppers on 1800 333 000.