Neighbours have described the horror of a car accident which resulted in the death of a 13-year-old girl, lifting the holiday road toll to six.

Residents on State Highway 2 at Eskdale - about 17km northwest of Napier - said there was "a huge bang" shortly before 3pm yesterday when a car and truck collided.

One man said he was inside his house when he heard what sounded like an explosion, before going outside to investigate. "I saw the car and I only saw half of it. The whole passenger's side was caved in, it looked like it was ripped out."

Another resident - who was looking at the accident site through binoculars - described the car as "a mangled mess" as moves were being made to tow the vehicle about three hours after the accident.

"It's just black," she said. "One side is completely gone and it looks like it's in a ditch. It's just horrible."

The male driver of the car suffered moderate injuries, ambulance staff said, and was taken to the Hawkes Bay Hospital for treatment.

A hospital spokeswoman last night said he was stable.

The truck driver was not injured.

The resident, who did not want to be named, said living on State Highway 2 meant she and her family were used to seeing speeding traffic.

She said she believed the car had backed out from a nearby beachside where people often went fishing.

"We drive out to 100km/h traffic and so we know to check twice - three times - before pulling out, otherwise you're going to have someone slam into you."

Another resident, Kathy Reid, said her husband had gone up the road on a motorbike to see what was causing a traffic jam. "It's been backed out about a kilometre and there's heaps of cops around. My husband said one of the cars had a tarpaulin over it."

There were traffic delays of up to three hours last night, as emergency services attended to the scene.

One lane of traffic was opened about 2 hours later, to help ease the traffic jam.

Meanwhile, several people injured in a multiple car crash last week remain in Hawkes Bay Hospital.

A truck and up to four cars were involved in the crash, on Monday, on State Highway 2 just north of Otane, southwest of Hastings.

A total of 11 people, including a 4-year-old boy, were taken to hospital. Seven of those remain there.

A 30-year-old man and a 33-year-old woman are in a serious but stable condition in the intensive care unit, a hospital spokeswoman said.

Five others are all stable and are now in general wards.

The spokeswoman said the others - including the 4-year-old old - had all been discharged.

The official holiday road toll runs from 4pm on Friday, December 24, until 6am next Wednesday.