Police respond to serious incident near Wellington region's Wainuiomata

Police have confirmed they shot a man in Wainuiomata today, after he was seen holding a weapon to a woman's neck and threatening to harm her.

In a statement, police said they were called to a suspected family harm incident at a Coast Road property at about 11.45am. Police negotiators were among those deployed.

When they arrived a man was behaving in an agitated manner and was seen holding a weapon to a woman's neck, police said. It was not a firearm.

The man continued threatening harm to the woman and at about 1pm police shot the man once.

He was provided with medical assistance but died at the scene, police said.

The woman involved was not injured but was understandably shaken by what had occurred, police said.

Superintendent Corrie Parnell said it was understood the man and woman were in a relationship. Both parties were known to police.

He extended his condolences and thoughts to the family of the man who died. "It's a tragic outcome for all involved," he said. Members of the man's immediate family were present, he said.

There were extensive negotiations before the shot was fired, Parnell said.

The man was "highly agitated", he said.

Police said they would have a large presence in the area to reassure the public.

Parnell said: "We understand that fatal police shootings… are frightening events, particularly for the local community, who will also be shaken at this time. There will be a large police presence in the area to provide reassurance not only today, but in the days to follow".

"A fatal shooting is an outcome nobody wants, and will have significant long-lasting impacts on both the officers involved and their families.

"Quite frankly, none of our people come to work each day for this outcome. So in the fullness of the investigation we will establish what has unfolded here, that ultimately has resulted in someone losing their life today."

Police have a "suite of tactical options" and a risk assessment would have been carried out, Parnell said.

"Each and every one of our officers is trained to assess what is happening in front of them. First and foremost, they must establish the threat environment… not only to individuals, but the wider public is critical, but also themselves… they need to establish very quickly as part of that assessment, the exposure - is it very real, immediate, and do we need to take action there? And come to that conclusion in terms of what they're forming in their mind.

"The next part is they will be required to make a determination - what is the necessity now for me to act and take action? And lastly… what is the proportionate and appropriate response with what I have available to me, tactically as a police officer, to deal with this situation?"

Several investigations are now underway and the matter has also been referred to the Independent Police Conduct Authority.

Cordons will remain outside the Coast Road property for some time - likely days - with a scene examination underway. Coast Road was cordoned off south of the Wainuiomata Golf Club.

'We could hear the police yelling'

Wainuiomata resident Elizabeth Lister told RNZ a woman ran out of a car towards her neighbours' house and believed the woman was being threatened at knife point by a man.

"I heard this loud car coming down the road... and I thought that's just a stupid guy and before he hardly even stopped outside ... the girl opened the door and she ran up the driveway.

"It looked like he threw a rock or something at the windscreen of the car, then it wasn't long ago after that the police arrived.

"We could hear the police yelling drop the knife, drop the knife."

Moments later she heard a gun shot.

The woman was then taken away by an ambulance "screaming her head off".

The armed offenders squad were still on Coast Road, Lister said. She said there were about 12 to 15 officers at the scene.

Earlier, two armed officers visited Lister's home and asked if they could get in the bushes to get a better view.