Police have knocked on six families' doors due to fatal crashes on our roads this weekend but are hoping they don't have to do any more.

Last night, with still a day to go, the road toll stood at six - already one more than the entire official Queen's Birthday holiday period last year.

Yesterday afternoon, one person was killed after the vehicle they were driving struck a tree on Dun Rd, near Kaingaroa Forest.

Earlier, a man was killed and four people including a mother and her baby were injured in a two-vehicle smash in northern Wairarapa, near Mt Bruce, just before noon.


And in Mangere East about 9.15am, two people had to be cut from a car after it crashed into a tree on Ferguson St.

A 16-year-old was in a critical condition and a 9-year-old and another person were seriously injured. Four people were in the car.

Alex Tonga was enjoying a few drinks with his mates when a car kept "zooming up and down" the street in South Auckland where he lived.

"The driver was probably doing 120 or 140ks, I don't know, but I was thinking he was either drunk or crazy," said the 16-year-old, who also saw the VR4 speeding around the neighbourhood about 2am.

On Saturday, a person was killed in a three-vehicle crash on State Highway 1 at Greta Valley, between Christchurch and Kaikoura.

About two hours earlier a motorcyclist died after crashing into a parked vehicle on Castlebane Drive in the Auckland suburb of Flat Bush.

A 64-year-old Kaikoura man was the first road fatality this holiday weekend. He was killed and several others, including a pregnant woman, were badly injured in a four-car crash on SH1 north of Dunedin just before 6pm on Friday.

The second death occurred early Saturday when two cars collided on SH3 near Te Kuiti. One person died and two others were injured, one seriously.

Last year five people died on the same holiday weekend. The official Queen's Birthday weekend period began at 4pm on Friday and ends 6am tomorrow.

National road policing manager Superintendent Steve Greally said everyone had to play their part in staying safe while driving to ensure no one else was killed or injured.

"The last thing our staff want to be doing is more knocking on the doors of friends and loved ones this weekend to deliver the awful news that someone they knew and loved has died."

Mr Greally said police would have a highly visible and active presence on the road, using a mixture of prevention and enforcement to focus on high-risk driving behaviour.

All drivers stopped could expect to be breath-tested and police would be checking everyone in the car is wearing their seatbelts.

"Police and our road safety partners cannot do it alone. We need the public's help to keep the roads safe. There has been a high number of deaths and serious injuries on our roads this year, leaving a devastating impact on a number of families and communities. We want to stop that from happening to other families this weekend."

Mr Greally urged motorists to drive to the wintry conditions.