Emergency Services are responding to a serious crash in Raetihi that has closed part of State Highway 4. 

A police spokesperson said they were notified just after 2pm that a car had collided with a tree between Valley Rd and Managarewa Rd. 

The driver has serious injuries and a helicopter has been sent to the scene. 

Waka Kotahi said the highway has been closed at the intersection with Seddon St, and police expect it to remain blocked for some time. 

Motorists travelling through the area are being told to expect delays and to plan their journey accordingly. 

Raetihi is a small town in the centre of the North Island, located at the junction of State Highways 4 and 49 in the Manawatū-Whanganui region.