Police have asked for the public to help with information on the whereabouts of Steven Keith Pengelly, 39 who they want to interview after a man suffered a serious cut to his throat in Nelson.

The incident took place in a house in Washington Valley Road, Nelson, about 4pm on Friday.

Pengelly is Caucasian, about 178cm tall and is considered very dangerous. Police have advised the public not to approach him.

Pengelly is from Wellington and is believed to have been in the Nelson area for about three days prior to the incident.

The victim is in a stable condition in Nelson Hospital.

Any sightings of Pengelly should be reported immediately to police by calling 111. Anyone who has any information on his whereabouts is also asked to call the officer in charge of the inquiry, Detective Sergeant Mark Kaveney of Nelson CIB, ph 546 3840.

Information can also be provided anonymously via Crimestoppers on 0800 555111.

St John Ambulance team manager Jon Leach said the 51-year-old victim was collected from the dairy in Washington Rd, bleeding from a "relatively deep laceration across the throat" that appeared to have missed his major arteries "but his airway was probably exposed".

He was conscious and taken to Nelson Hospital in a stable state.

Kaveney said the man had been injured at a private house and the man they were looking for had left the scene when they arrived.

It was a "very nasty" injury that could have been life-threatening, he said.

Police did not know what had been used to cause it and no weapon had been found.

"We believe we're looking for one person. We're still trying to determine the identity of that person."

Kaveney said a team of detectives and uniformed police had spent last night checking areas of the city where the man might be found, and talking to "the local suspects round town". Police did not know what had motivated the attack. "It's still at the early stages. We've got a lot of work to do in relation to it."

A Washington Valley resident, who did not want to be named, said this morning that the victim was well-known in the community for having drinking sessions at his home.

Police had been there many times, she said, usually to deal with the man himself or when he was in the company of the same small group of drinkers. The man, who was "totally different when he's not drinking" had lived in the house for a long time.

- © Fairfax NZ News