Traffic was delayed on State Highway 29 after a car collided with a vehicle parked on the side of the road yesterday afternoon.
Deanna Way, who was behind the wheel of a black four-wheel-drive, was "shocked" but not injured, said her son, Timothy Way, who was on the scene shortly after the accident.
Police constable Mark Sanders said Mrs Way was travelling south-west towards Maungatapu when she clipped the back of a parked Toyota just before 3pm.
The silver car had been pushed up on to the steep grass verge and the black four-wheel-drive had spun to face the driver's side of the stationary car, smashing its back windscreen and a window.
Mr Sanders said the police were trying to contact the owner of the silver Toyota, which was believed to have been parked there for several hours.
The police did not know why the vehicle had been parked on the side of the highway, he said.
Maungatapu Rd resident Brett Jobson said he had heard the loud bang and thought it sounded like the thud of cars coming together.
"You could tell it was a car crash straight away," he said.
Timothy Way said he received a call from his mother shortly after the crash.
"She said she'd had an accident. She sounded pretty shocked and pretty freaked out."
North-bound traffic was limited to one lane and south-bound traffic was diverted on to the overbridge and through Maungatapu as the two vehicles were removed and police worked to clear the area.