Southbound and northbound travellers are able to move through the Cooperabung Ranges alternatively under what the Transport Management Centre calls "stop slow traffic conditions."

"It will alleviate some of the issues, but the situation is going to go on for hours," a spokesman said.

10.15am: Motorists wanting to use the Settlement Point or Hibbard ferries to cross the Hastings River at Port Macquarie face significant delays following a double fatality on the Pacific Highway at Kundabung. Read more

9.50am: Police are appealing for people to have patience following the tragic accident on the Pacific Highway.

It would assist them if calls were made to 13 27 01 for traffic updates rather than police stations. At this stage it is believed the highway will be closed until at least 2pm.

Alternate routes are the Maria River Road although there are delays at both Hastings River ferries at Settlement Point and Hibbard causing traffic to build up.Another route is via Walcha to Armidale.

Alternating stop/slow traffic conditions are now in place on the Pacific Highway in Kundabung following a fatal accident.

One lane has reopened with motorists taking turns to pass the incident. Traffic is heavy in the area and motorists are experiencing significant delays.

All diversions have been lifted however motorists are still advised to travel via the New England Highway as an alternative.

Police remain on site continuing their investigation into the incident.

Motorists should exercise caution passing the scene.

9.25am: Police have confirmed a mother and her 12-year-old daughter have been killed in Friday's fatal crash on the Pacific Highway at Kundabung.

The woman's husband and daughter, also in the car, were injured along with the driver of a northbound truck. he has been flown to Newcastle's John Hunter Hospital with critical injuries.

None of the people involved in the horror crash were locals, police said.

State Emergency Service crews from Kempsey and Port Macquarie were called to the scene, 25km south of Kempsey, about 5.30am on a single lane stretch of the Pacific Highway.

Police and emergency services remain at the scene

It is expected one lane of the highway will be opened about 9.45am. Traffic is backed up about 5km both ways.

Meanwhile traffic queues on alternative routes into Port Macquarie are lengthy. There is a 500m queue on Port Macquarie's Settlement Point ferry and motorists have been in line for more than 90 minutes.

8.30am: Westpac Rescue Helicopter spokesman said the truck driver, believed to be in his 40s, was taken from Port Macquarie to Newcastle's John Hunter Hospital in a serious condition. He reportedly has multiple injuries.

7.25am: The Pacific Highway is closed in both directions in Kundabung due to a fatal accident near the top of the range after an accident in which two people have died.

A NSW Police spokeswoman said it was feared there could be third casualty. The cause of the crash was not immediately known.

A helicopter was attempting to land on the highway just after 6am to treat other people who had been injured in the crash.

Light vehicles are advised to use the Oxley Highway, New England Highway and Waterfall Way for travel between Port Macquarie and Raleigh.

Heavy vehicles are advised to use the New England Highway and Gwydir Highway (via Glen Innes) for travel between the Hunter Region and Grafton.

Emergency services and traffic crews are on site.

Due to the serious nature of the incident the highway is likely to be closed for some time.

For the latest traffic information, visit www.livetraffic.com or call 132 701.

At least two people have died in a crash between a car and a truck on the Pacific Highway near Kempsey, police say.

The crash occurred at Kundabung, about 15 kilometres south of Kempsey, at 5.15am.

The highway has been closed in both directions at the accident scene while police and emergency service workers attend the scene.

The Transport Management Centre said the highway was expected to be closed for some time "due to the serious nature of the incident".