An operation to clear a chemical spill after a crash on State Highway 1 at Ohakea, Manawatu, has hit complications.
A chemical tanker carrying caustic soda crashed about 6am after it swerved to avoid hitting a pedestrian on the road.
The truck still hit the 22-year-old pedestrian from Feilding and then overturned into a ditch, killing the 48-year-old Wellington driver.
The operation to clear the caustic soda leaking into the drainage ditch from the tanker was proving difficult, said Sergeant Phil Gillbanks, of Feilding police.
The tanker contained 16,200 litres of caustic soda, and while another tanker was arriving soon, it would not be able to hold all of the chemical.
A specialist chemical tanker unit was travelling down from the Bay of Plenty but severe weather on the Desert Road had caused delays, Mr Gillbanks said.
"We are having to proceed with caution as we don't know whether the current leak is just from the overflow or from a much larger rupture that we can't see.
"We need to be certain that if we lift the tanker before it is emptied, that we will not be causing any environmental hazard."
A logging expert was on his way to the scene to remove three trees which had fallen on the tanker.
SH1 at Ohakea remains closed, with a diversion in place.
The accident comes after a head-on crash on State Highway 30, 11km east of Benneydale, about 2pm yesterday which killed four people and injured three.
Those who died included Lucan Ryder, 29, Patricia Matthews, 30, and Monique Ryder, nine, who were all in the same car.
Two other children in the car were injured, police said.
One woman was killed in the other car, and a man was taken to Waikato Hospital.
Police would not name the woman until she was formally identified.
A Waikato Hospital spokeswoman said that a 62-year-old man had been transferred from the hospital's emergency department and was in a stable condition in a ward.
A four-year-old boy was due to be transferred by air ambulance to Auckland's Starship Hospital overnight but it was too foggy for the plane to land, the spokeswoman said.
The boy was now in Waikato Hospital's intensive care unit waiting to be transferred and was in a serious condition, she said.
A 10-year-old boy was in a stable condition in a ward.
Waikato highway patrol Sergeant Marc Hepworth said police were searching for a motorist who was first on the scene but had driven off because he was running late for a rugby match.
Early this morning, one person died in a three-car crash in Auckland.
The accident happened shortly before 1am on Auckland's southern motorway, about 20 metres north of the Princess Street off-ramp, northern police communications Inspector Shawn Rutene said.
One person died at the scene and two others were taken to hospital.
