An elderly man is dead following a three-crash at Ohau, south of Levin.
Police say the crash happened when a north-bound Toyota Hilux crossed the centre line and crashed into two south-bound cars on Friday.
A 76-year-old man, who was travelling south, was flown to Wellington Hospital but died shortly after.
Two other people with moderate injuries were flown to Palmerston North Hospital, while a fourth person received minor injuries and did not need hospital treatment.
Both lanes of State Highway 1 were closed, causing a traffic backlog, but have since reopened.
Police are appealing for witnesses to the crash.