Dunedin's West Harbour community is in shock after two children were seemingly shot dead by a man who had protection orders against him.

Photo: NZ POLICE

Bradley and Ellen Livingstone, aged nine and six, died from gunshot wounds at their Kiwi Street home in St Leonards on Wednesday night. A 51-year-old Milton prison worker then appears to have turned the gun on himself.

Police will not yet release his name until they finish contacting relatives overseas. However, they confirmed on Thursday that he is the estranged husband of the children's mother, Katharine Livingstone, 49, and that their relationship ended in May last year.

Police received an emergency call about 9.55pm on Wednesday after neighbours heard gunshots coming from the home. The Armed Offenders Squad was deployed and the bodies and a shotgun were found at the scene.

Police said the children lived at the house with Ms Livingstone. Neighbours said she took refuge next door when the man confronted her with a gun.

Dunedin police commander Greg Sparrow called the events a tragic set of circumstances. He said the man worked at the South Otago prison and was well known to police.

Photo: RNZ

"The family had been known to us for a number of domestic incidents. What I can tell you is that he had been arrested on two previous occasions for breaching a protection order and we'd put him before the court."

Mr Sparrow said the man was given diversion on 7 August last year and on 14 September was discharged without conviction. Police are investigating how he was able to go to the house with a gun he didn't have a licence for.

About 15 police and ESR staff are working on the investigation and a forensic examination of the scene is under way.

Neighbours of the family told Radio New Zealand the man came back to the house to confront Ms Livingstone and shot the children and himself. One said the man had previously threatened to kill the family, but Mr Sparrow said he could not confirm that on Thursday.

A woman who lives next door to the Kiwi Street house said she and her husband heard multiple shots, before her husband tried to take the gun, but was shot at and had to retreat.

The children's school, St Leonards, has only 72 pupils. Board of trustees chair Ceri Warnock said the school rang all the families and about half came in with their children to grieve and try to make sense of what's happened.

Photo: RNZ

Corrections aware of breaches

The Department of Corrections said the Milton man had worked in administration at the prison since 2007.

Acting chief executive Jeremy Lightfoot said the man told Corrections in August 2013 about his first protection order breach and after the second breach in September was stood down for a period. He said the man had also been given a final written warning.

Photo: RNZ

Mr Lightfoot said the department felt that, in the circumstances, it was better for the man to be stood down during his court cases and then allowed back to work while being given counselling.

Women's Refuge says its members are appalled that a man with a protection order was able to get a gun. Spokesperson Kiri Hannafin said on Thursday that such breaches are often an indication of escalating violence in a relationship.

"That's one of the reasons we're constantly urging the criminal justice sector to act consistently and with the full force of the law to breaches and protection orders, because it's a serious offence. We are concerned that often the seriousness of it is not considered adequately."

Ms Hannafin said there is a proven link between protection order breaches and domestic violence killings.

Help available

Dunedin's Collaboration Against Family Violence organisation is reminding the public that help is available for those who find themselves in violent situations.

Spokesperson Rob Thomson said he is greatly saddened by what has occurred. He said there is often a desire to blame individuals or services, but people need to take responsibility to ensure that such things don't happen again by calling the authorities.

Mr Thomson said it is common for violence to worsen after a separation, and many killings happen at that time.