There are unconfirmed reports a car which crashed near Foxton yesterday killing a 14-year-old boy and a 20-year-old woman may have earlier been racing another vehicle.

Loiuse Reichenbach, 20, from Foxton Beach and Bailey Hohepa Kinita, 14, from Shannon died when the five-seat Ford Telstar they were in - along with five other people - crashed just after 5am on Foxton Beach Rd.

It was one of two double-fatality crashes on North Island roads yesterday. A collision at Karapiro yesterday afternoon also killed two people.

Detective Sergeant Sarn Paroli said it was too early in the investigation to draw any conclusions into how the crash near Foxton happened.

"There is some unconfirmed information circulating that the car had been racing with a second vehicle before the crash but at this stage that is speculation. That information will be fully investigated but until then that aspect is unconfirmed," he said.

"What witnesses have told us is that the car had been seen with another white vehicle earlier in the morning; in what context it is unclear. We understand there were two men in that white vehicle and we are keen to speak to them."

The Herald understands that car was driven by a local male known to the group in the Ford.

Miss Reichenbach, a recently qualified occupational therapist, is believed to have been sitting in the front footwell of the car, next to the front-seat passenger and the 19-year-old driver, when the crash happened.

Four others were crammed into the backseat and at least one, Bailey, was flung from the car when it rolled several times.

St John Ambulance officers were not able to revive either of the dead, but took the other five to Palmerston North Hospital, two seriously hurt and three with moderate to serious injuries. A male and female were later discharged, while three men - including the driver - were flown to Wellington Hospital, and remained in intensive care in a serious condition this morning.

The Police Serious Crash Investigation Unit will return to the scene today to continue with their examination and the vehicle will be examined.

Detective Darcy Parke said this was the sort of horrific crash that New Zealand was experiencing far too often. "It is such a senseless waste of young lives and will have huge impact on so many families.

"The mere fact that there were seven people travelling at speed in a vehicle designed for five shows that there are still too many young people out there risking their own and others lives on our roads."

Foxton deputy fire chief Michael Clement said firefighters found the injured both in and out of the wreck.

While the car was up the right way, it was obvious it had rolled several times as the roof was smashed in and there was debris all over the road.

Mr Clement said three of the passengers had been "ejected from the car", including the Bailey, who was lying in the middle of the road.

Firefighters had to cut Miss Reichenbach from the front-seat area. She was lying on top of a male passenger, who had his seatbelt on.

Most of the occupants in the car, who were aged between 14 and 23, were from the Foxton and Shannon area and had attended Manawatu College.

Principal Bruce McIntyre said Miss Reichenbach was a former top student and staff were saddened by news of her death. "She was a very quiet, studious girl and very popular with staff."

Bailey was a Year 11 student who had started at the school only three weeks ago. "I was impressed with him at his school enrolment meeting ... He was just someone who had a lot of potential and I thought, 'Oh this kid is going to do well here', but unfortunately it's not to be."

Last night, friends were grieving for the pair who died. Miss Reichenbach's friend Tia Kuiti, who was in the car and escaped with minor injuries, wrote on her Facebook page: "Im sorry Lou i did try ta get u out i was there with u til the end, love u forever."

It is understood Miss Kuiti also tried to revive Bailey with mouth-to-mouth resuscitation.