Crash experts will investigate why an elderly man yesterday travelled onto the incorrect side of the busy John Renshaw Drive in a 40k/mh zone before crashing into two four-wheel drives, killing himself and his friend.
The deaths of the man, 74, and woman, 40, who were friends from Kurri Kurri, brings the toll to seven deaths in 18 months on the major arterial route between the F3 Freeway and the Coalfields.
Newcastle crash investigation unit officers spent hours at the scene of the crash yesterday attempting to discover how and why the white Hyundai Excel, which was travelling east, went onto the incorrect side of the road about 200 metres from the George Booth Drive roundabout 9am.
The section of the road has a 40k/mh speed limit as work on the Hunter Expressway, which crosses the road a few hundred metres away, continues.
It is believed the driver of a white Landcruiser "troop carrier" travelling west swerved to the right to miss the Hyundai, but was clipped by the hatchback and rolled.
The impact caused the Hyundai to spin into the path of a black Mitsubishi Triton.
Both drivers of the other vehicles were treated in hospital for minor injuries.
The female passenger of the Hyundai was pronounced dead at the scene as Cessnock Volunteer Rescue Association members worked with hydraulic spreaders to cut out her critically injured friend.
He was flown by Hunter Westpac rescue helicopter to John Hunter Hospital but later died.
It is believed the pair were travelling from Kurri Kurri to Green Hills.
The accident blocked the road for seven hours.
The deaths bring the toll to seven along John Renshaw Drive since December, 2010.
A man was injured and trapped inside his car after a head-on collision at Beresfield last night.
About 6pm a Nissan Patrol four-wheel-drive and a Daihatsu Charade collided on the New England Highway, near the intersection with Weakleys Drive.
The man was trapped by his legs and bleeding from the nose when police and paramedics arrived.
He was taken to John Hunter Hospital.
The New England Highway was closed for several hours last night.