Te Anau man sparked an Armed Offenders Squad callout on Thursday night after threatening to kill himself with a gun.
Sergeant Pete Graham, of Te Anau, said the man had "threatened to commit suicide" and police were alerted to the man's behaviour by family members just before 7pm at a house on no-exit Kakapo Rd.
He said the man, in his 70s, was not brandishing a gun but firearms were known to be in the house.
Sgt Graham and another Te Anau officer were joined by a Lumsden officer, awaiting a full AOS squad from Invercargill.
The squad arrived about an hour later and the scene was "cordoned and contained" and the man surrendered to police about 9.30pm.
He was then taken into custody and transported to Invercargill, where he was undergoing a routine mental health assessment with an emergency team from the Southland District Health Board yesterday.
Sgt Graham said inquiries were continuing and it was not yet known if the man would face charges.
