One man is confirmed dead after a light truck was hit by a train just north of Woodville, in Tararua District.
Constable Christopher Wakelin said the incident happened at about 5pm at a rail crossing on Powdrell Rd, off State Highway 2.
The man may not be the only fatality, and had not yet been cut from the truck.
"It was hit pretty hard, so we have a lot of area to cover," Wakelin said.
Police, fire, ambulance and KiwiRail staff are at the scene this evening.
Wakelin said the train was travelling from the direction of Dannevirke towards Woodville at the time.
Powdrell Rd has been closed while a scene examination is carried out.
Police Acting Inspector Bruce Mackay said "a truck has crossed onto a crossing from a dead-end side street. The impact pushed the small truck off the road.
"The person was alive, but now confirmed fatal."
Meanwhile, a man is in hospital with critical injuries after his motorcycle crashed on the Featherston side of Rimutaka Hill Rd, north of Wellington, about 8pm this evening.
A Westpac Rescue helicopter took the man to Wellington Hospital.
One lane of State Highway 2 was closed for about two hours after the crash.
No other vehicles were thought to be involved, police said.