A horror crash near Gisborne last night resulted in the deaths of four people, including three who could not be freed from their burning vehicle.
A 33-year-old woman was killed when the van she was driving collided head-on with another vehicle on State Highway 2 at Tairawhiti, at about 9.15 pm.
The second car exploded into flames, killing three people inside.
Passing motorists tried to help the three but were unable to free them from their seatbelts before the Ford Explorer was enveloped in flames, police said.
The driver and sole survivor of the crash, a 59-year-old man, was in Gisborne Hospital in a serious, but stable condition.
The woman was travelling to her parents' home in Whatatutu from Gisborne after being the sober driver for the night for one of her friends.
Senior Sergeant Moera Brown said it was believed the Explorer caused the crash by crossing the centre line. A
"The occupants were from Putaruru and were travelling to Gisborne to visit family. They have a large and extended family in various parts of the North Island who are in a state of shock"
A forensic examination would be required to establish the identity of the three passengers from the Explorer, Brown said.
Meanwhile, a pregnant woman was killed yesterday in a two-car crash north of Timaru which closed part of State Highway 1 for several hours.
The 24-year-old died at the scene and her husband, who was the driver, was thrown from the vehicle, sustaining serious injuries.
Their two children, aged 4 and 5, were in the back seat and were treated for minor injuries.
Three people were sent to hospital, and a South Canterbury District Health Board spokeswoman said one was still in the intensive care unit in a serious but stable condition.
Two others are in stable conditions, but will remain in Timaru.
On Friday, Annalese Bacon, 17, died when the driver of the car she was travelling in lost control and the vehicle flipped in Reporoa.
National Manager of Road Policing Superintendent Carey Griffiths said that despite constant messaging about the dangers of speed, alcohol and failure to wear seatbelts, they remained consistent factors in serious and fatal crashes.
"People being killed and injured don't just start speeding, drink driving and not wearing seatbelts on holiday weekends," he said.
"Families, friends, whanau all see these behaviours on a consistent basis and it is time we all started taking more responsibility".
Griffiths said the police could only do so much.
"Our message that road safety is everyone's responsibility means just that" he said.
"If you see your friends and family not following the basic rules, challenge them on it. You may save a life."
The official holiday period for Labour Weekend 2012 began at 4pm 19 October and ends at 6am Tuesday 23 October.