One person has died after their car collided with a tree on Windwhistle Road (State Highway 77).

Police say the accident happened between Nelsons Road and Washpen Road at 2.45PM.

A helicopter was called, but was turned back following a report from the scene of the fatality.

The road is blocked and motorists are asked to take alternative routes where possible.

NZTA says the state highway is closed from Leaches Road to Downs Road.

It is urging motorists to delay travelling.

The serious crash unit is investigating.