A newborn baby is among the dead in a horrific car crash in South Taranaki this morning.

Six people are dead and two have critical injuries after a horror crash near Waverley. Police confirmed about 3pm that there were now six fatalities.

Five of the victims are adults and one is a new born baby.

Four adults in a vehicle travelling north were pronounced dead at the scene. The driver of the second southbound car and a new born baby also died at the scene.

Police said the front seat passenger of the southbound car - a woman - was airlifted to Wellington Hospital with critical injuries. An 8-year-old girl has been taken to Waikato Hospital for treatment.

Police said the Serious Crash Unit was still investigating the circumstances of the crash, but said it was clear that the vehicles have impacted head on.

"At the time of the crash, the weather was clear and the road was dry. The crash occurred on a slight right hand bend of the road."

Police called the crash "devastating.''

"The tragedy will affect a large number of people in our community. Our sympathies and condolences go out to the family, friends and loved ones of those involved.''

Officers said the priority now was making sure support was provided to those who need it following the "heartbreaking'' crash.

Whanganui Sergeant Colin Wright said four people were in each car that collided head-on on State Highway 3. Four of the dead were elderly. They were travelling west, towards Hawera, when the two cars collided on a sweeping bend near Waverley Racecourse shortly after 11am. Two people from the other car are also dead.

 

"They're still being treated [and are] going to be going to various hospitals," Wright said.

"At the moment we're just investigating exactly what's happened."

Two rescue helicopters have landed at the crash and a third is on its way. Two fire engines, three ambulances and multiple police officers are at the crash.

Wright said the road will be closed for a number of hours.

Cars are being diverted off SH3 down Ihupuku Rd and motorists are advised to avoid the area.

A local woman leaving work 500m from the crash described it as "a mess".

A local woman described the crash scene as "a mess". (Photo / NZME)

She said it looked like a vehicle had crossed the centre line and collided head-on with another vehicle.

The road was wet and slippery, she said.

A staff member at Waverley Four Square said the roads were still slippery after a big frost this morning.

Waverley is in the South Taranaki district, 44km northwest of Whanganui.

Taranaki police this morning warned drivers about ice on the road, after four crashes since 5am.

"We need motorists across Taranaki to be extremely cautious on the roads this morning after four crashes caused by ice on the road since 5am," police said.

"Any patches of road which appear wet will likely be ice and should be treated as such.

"Police are also advising people to check their vehicles and tyres are roadworthy and ensure all windows are completely clear of ice before getting behind the wheel."

Today's crash follows a fatal truck smash in Waverley on Monday.

As of yesterday 187 people had died on New Zealand roads so far this year, up from 183 at the same point in 2017.

Over the past 12 months 382 died, up from 343 in the previous 12 months.