Travellers faced delays on Sunday afternoon after a fatal crash near Otaki on State Highway 1.

The driver of a truck involved in a fatal crash on State Highway 1 swerved to avoid an oncoming vehicle, the haulage company says.

The crash, south of Levin, caused significant delays for holiday travellers.

The road reopened about 5.30pm under traffic management and a reduced speed limit, but would be closing again at 10pm so the truck could be removed.

The Hilton Haulage truck landed in a cemetery as a result of the crash, which also involved up to two cars. It happened just before 2pm on Sunday.

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Hilton Haulage general manager Alle McGrath posted on the company's Facebook page and said the driver, David McNeill, had not been seriously injured, but there was a fatality in another vehicle following a suspected medical event.

The truck, a Kenworth Curtainsider, was travelling south towards Ōtaki when it swerved to avoid a car that crossed the centre line, the post said.

The truck jack-knifed, partly landing in a cemetery.

The company was flying the driver home on Sunday night.

SUPPLIED A truck has landed in a cemetery in the crash near Levin.

The NZ Transport Agency warned there were no viable detours available, people should avoid travel if possible and power lines were down.

Traveller Dan Boyd was stuck in the queue about 2km north of the crash site.

He said people were out enjoying the sun, eating real fruit icecream, and the local fruit shop, Brownacres Market, was handing out free bananas.

There was traffic passing from the south as traffic management let people through, and a few had left the queue to take the alternative route through the Remutaka Ranges.

Supplied People make the most of the sun as they sit in the queue.

Hearing the crash was fatal put a new perspective on the wait, he said.

"The wait in traffic doesn't really matter as long as you can still be present and many thoughts are with the family who passed away at the time when you're all meant to be with your friends and family at this time of year."

St John Ambulance said six people were treated for minor injuries and one for moderate injuries.