A female pedestrian died when she was hit by a truck at the intersection of London St and SH3 in Wanganui last night.
Firefighters who attended the scene said it was unclear what she was doing on the road, as the nearby walkway was fenced off.
Emergency services were called to the scene at 11.10pm.
Witness Christopher Cape was getting petrol at the Gull Service Station near the intersection when he heard the truck driving up the bypass and coming to a stop before it reached the merge section.
"I saw it drive reasonably slowly up and then it stopped, and I thought, 'good grief, that's odd'," Mr Cape said.
"The door opened, the driver got out and walked back to inspect his rig. I thought 'oh, it's broken down'."
Two cars were stuck behind the truck as it blocked off the bypass, so Mr Cape called *555 to let them know there had been a breakdown. He was then told they'd received a report that a woman had been hit by the truck.
St John Wanganui territory manager John Stretton said the woman was dead when paramedics arrived.
Firefighters assisted police and the funeral directors in recovering her body, but none of the fire service's equipment was needed, senior station officer Jemal Weston said.
They also helped screen off the area while police conducted a scene investigation.
"The police were unsure how she ended up there because there was no footpath there," Mr Weston said.
There was walkway behind a high fence at the top of a steep, grass bank behind the bypass, and it was unclear whether the woman had climbed over the fence or come up from the road, he said.