The crash happened on State Highway 1 near Waipu at Uretiti about 1pm. SH1 was closed for several hours, but has now been re-opened, although a speed restriction has been put in place.
Speaking at a press conference at Whangarei Police Station today, Northland road policing boss Murray Hodson said the crash was a result of the driver of the car making an error of judgement, with fatal consequences.
"This is a tragedy - a catastrophic scene - and there will be a number of people who will be affected by this incident."
The injured child had been taken from the scene by Northland Electricity rescue helicopter.
Mr Hodson said there were already reports of drivers speeding to get to their destinations after being delayed by the crash.
"Please slow down. We want you to get to your destination safely and police do not want to attend another crash like this one. We also don't want to tell other families that their loved ones have died on the road this Christmas."
Skid marks on the road can be seen at the scene of the fatal crash. Photo / Peter Carr
A woman living about 500 metres south of the crash scene, Lee Hanna, said the truck and trailer unit were still upright with a load of logs intact among trees beside State Highway 1 but the cab was sprawled on its side, jack-knifed across on lane of the road wheels facing the road.
She could see a car upside down about 20 metres south of the truck, also among trees and beside the coastal side of the highway.
"It's a dreadful mess - there's a lot of squashed metal all over the road," said Mrs Hanna, a health and safety consultant, who was away at Ruakaka when the crash happened, and joined nose to tail traffic on a diversion route to get back home..
Photo / Daniel Hines
Pete Turnball, pilot for Northland Electricity rescue helicopter, said the crew transported the critically hurt boy to Whangarei Hospital.
A rescue helicopter had left the scene before 2pm, but returned about half an hour later, rejoining two ambulances and three fire trucks.
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The crash scene was south of the Waipu Golf Club, about 100m from the end of a passing lane on a recently-resealed stretch of highway.
A manager at the Department of Conservation's Uretiti Beach camp-site north of the crash scene said campers among the almost 200 people staying there were "quite shaken", although she was unaware of any who witnessed the carnage.
"It's a real tragedy," she said, adding that she was hoping for a safe exodus from the camp on January 2, when it traditionally emptied out after New Year's celebrations to make way for family groups.
Photo / Daniel Hines
The woman, who did not want to be named, said no large family such as may have been involved in the crash was booked to stay at the camp tonight.
But she said that did not necessarily rule out the camp as an intended destination for the victims.
No traffic was being allowed to reach the camp from the south, but she said police were letting through vehicles heading to it from the north.
The fatal crash has closed State Highway 1 between Rosythe and Mountfield roads.
The crash happened about 1km away from the Uretiti Beach Camping Ground, manager David Archer said.
He said the crash was "horrific" and had left visitors to the camp ground wondering what had happened.
"The road is closed, there has been no traffic for about two hours going past... There is a truck up there that looks like it has been damaged."
Mr Archer said he was not sure whether the passengers of the vehicle were heading to the campsite.
"I have no idea whether they were heading here or just passing by, it is the main road so there is a huge amount of traffic passing backwards and forwards to Whangarei.
Photo / Daniel Hines
- additional reporting Northern Advocate