Key Points:

A man who threatened to harm himself and police sparked an armed offenders squad callout to the Waikato town of Putaruru last night.

Police were called to a house in Scotia Glen around 7.20pm after the 45-year-old occupant called police saying he had a firearm and intended to harm himself.

The AOS was called in, along with police negotiators and officers from Tokoroa, Rotorua and Taupo.

An area of Putaruru was cordoned off for three and a half hours while police negotiated with the man, who refused to leave the house and threatened to injure police.

Tear gas was eventually fired into the house around 10.30pm and the man surrendered within minutes.

He was treated in hospital for injuries and before being taken into police custody to await follow-up action with local community health agencies.

No firearm was located during a search of the house.