One person has died and five others were injured after a police chase ended with a driver crashing into another car in Christchurch.
The crash at the intersection of Idris and Glandovey roads happened just after 4am.
Police said they had signalled a Toyota on Papanui Road to stop because of the manner of driving, and pursued it for four minutes before it crashed.
It collided with a Hyundai at the intersection.
The driver and sole occupant of the Hyundai was critically injured and has died in hospital.
Of the five occupants in the Toyota, one has critical injuries and the other four serious to moderate injuries, police said.
"This incident is an absolute tragedy and our thoughts are with the family of the man who has died and with those who are injured," Canterbury Metro Area Commander Superintendent Lane Todd said.
"The decision whether or not to pursue a fleeing driver is one of the most serious decisions our staff face on the frontline.
"We come to work every day to keep our community safe and the staff involved are deeply shocked by this event.
The roads remain closed as the Serious Crash Unit are at the scene gathering evidence and undertaking examinations.
"That work will assist the police investigation which is now currently underway. The incident has also been referred to the Independent Police Conduct Authority (IPCA) who will undertake an independent investigation."
The pursuit was still active at the time of the crash, he said.
He said the fleeing vehicle wasn't at "horrendous speeds, but they were over the speed limit".
He described the nature of the driving as erratic.
At this stage, police didn't believe the car was stolen.
"The pursuit initiated in Papanui road and ended where the crash was and took just over four minutes."
Watch: Police addressing the media
Following the release of a joint review into police chases with the IPCA in March, NZ Police said it would improve training to reduce officers' inconsistent approaches to chasing fleeing drivers.
Since then, additional training has been put in place which included a process that police officers had to go through - threat, exposure, the necessity to respond and then the response itself, he said.
"It was a comprehensive review with a number of recommendations and I think police agreed with all the recommendations and are in the process of implementing those.
"Officers have to go through a lot more training and oversight of that particular process."
RNZ's reporter at the site of the crash said a black vehicle had been crushed against a wall on the side of the road.
St John sent five ambulances and two first responder vehicles, and initially said they had taken eight people to hospital, but later confirmed there were six injured in hospital - two critically hurt, three seriously hurt and one moderately injured.
The intersection of Idris Road and Glandovey Road will remain closed for a number of hours with diversions in place.
Fendalton resident Sandra Francis said she was awoken by the incident.
"First thing I heard were sirens and then the most horrendous bang I've ever heard. I just yelled out to my husband 'let's go see if we can be of any help', we weren't of course because the police were here so quickly because they were chasing them. They were right on their tail."
She said police should not pursue vehicles in residential areas.
"I think they need to back off these young boys and just slow down and catch them down the track; not right here in the middle of the city and residential area. Look what's happened."