A police negotiation team is at a house in Blenheim where a man with a gun is holding a person hostage.

Police were called to the house in Park Terrace just after 5pm on Friday, Marlborough Area Commander Inspector Simon Feltham, said after a man arrived with a gun.

Feltham said it was a "family harm-related incident".

Two people were originally inside the house and one was able to get to safety, he said, but the other person remained inside with the man who was known to them.

No one had been injured, Feltham said, and police were focused on the welfare of the people inside.

Neighbours were asked to stay in temporary accommodation on Friday night.

There was no risk to the wider community, police said.

A section of Park Terrace is cordoned off and the public is asked to avoid the area.

rnz.co.nz