One person is dead after a crash involving a truck and a car on State Highway 3 south of Uruti this morning.

A spokesman from St John ambulance service said the car driver was dead by the time paramedics arrived.

He said emergency services received a call about the crash at 8.30am.

A rescue helicopter was placed on standby but was not needed.

The road is currently blocked and heavy lifting equipment is being brought in to move the truck.

Diversions are in place for light vehicles through Okoki Rd, to the south and Uruti Rd to the north.

Police said due to the large amount of work required to clear the scene and open the road, diversions were expected to remain in place until 5pm today.

Motorists should avoid the area if possible or plan for lengthy delays.

A roading crew was called up to help staff the diversions.

By midday, traffic was being allowed in one direction.

A New Plymouth Police spokeswoman said the crash happened in hilly terrain and contact with emergency services was affected by poor cellphone coverage.

- with NZPA