Police were alerted to the crash on State Highway 1 near the intersection with Ruahine Road around 12.42pm.
Two adults and another child remain in hospital with critical injuries after a van and car collided head-on near Mangaweka this afternoon.
The accident raises the unconfirmed holiday road toll to nine.
State Highway 1 between Waiouru and Bulls was closed to southbound and northbound traffic, but reopened just before 5.30pm.
NZTA warns to expect delays as traffic resumes.
Police thanked members of the public who helped, by taking control of the scene until emergency services arrived.The accident comes as many travellers are on the roads before the New Year's holiday.
A staff at a cafe near where the crash happened said the cafe was full of customers for at least an hour and a half.
Georgia Coleman, who works at the Dukes Roadhouse cafe, said it was mostly people who got stuck in the traffic.
"Everyone's just trying to work out what's going on, like obviously reading news articles, working out how long they're going to have to be waiting and like, sorting out plans and stuff like that."
Coleman said the roads were empty by about 3pm as most have left to take detours.
Hato Hone St John confirmed two ambulances, a first response unit, two helicopters and an opterations manager were dispatched to the scene.Earlier RNZ reported at least seven people have died on the roads since Christmas Eve.
In a statement Sunday, Police Superintendent Steve Greally, director of road policing, said seeing eight fatal crashes with nine people dead since Tuesday is incredibly frustrating.
"There's no excuse for any driver to be endangering their lives and those of others with unsafe behaviours.
"There are many families that have been affected by bad decision making from behind the wheel so far this holiday."
Greally said police would continue to be highly visible at high-risk locations over the holiday period.
"We can all work together to avoid unnecessary road trauma," he said.
