A horse had to be cut from a car after a crash on State Highway 3 this morning.

A horse has miraculously survived a freak accident which saw it end up in the back seat of a car near New Plymouth this morning.

One horse did die and another was later put down following a crash near the intersection of State Highway 3 and Mangorei Rd about 6.40am.

The crash happened after four horses escaped from a paddock overnight and three were hit by a south-bound car.

The highway was closed for two hours and diversions had to be put in place.

The 46-year-old male driver of the car, the sole occupant, was taken to Taranaki Base Hospital with head injuries, but was not badly hurt.

Firefighters used the jaws of life to cut one of the horses free from the backseat of the car while another was lying dead in the middle of the road.

The horse cut from the car survived the accident.

Acting Sergeant Andrew Stilton said the driver came around a bend and found the horses in the middle of the road.

''Three horses were hit and one's ended up in the vehicle.''

A vet sedated the horse before it was able to be cut free from the wreckage, he said.

The vet discovered one of the horses had suffered a broken leg in the collision and would have to be destroyed.

The injured driver received cuts to his head but was not seriously injured.

Stilton said police investigations into how the horses got out were continuing.

Firefighters, police, animal control and the horses' owner were at the scene.