Nearly a dozen high-powered weapons were stolen from a house in Northland last night.
Residents of a house in Dargaville came home at 5.30pm to find 11 submachine guns and assault rifles had been stolen from them, as well as several electronic items.
A white station wagon was seen near the house, and police want to hear from anyone who may have seen a similar car driving in a suspicious manner.
The owner of the property is a gun collector, and police believe the guns were stored properly.
Senior Sergeant Rob Huys said police are "very concerned that these firearms are now likely to be in the hands of the criminal fraternity and the obvious risk that this poses".
He said the owner and his wife are "quite distressed" and they are providing support to them.
An investigation has continued throughout much of today, involving CIB staff, frontline police officers and scene of crime officers, who have carried out a forensic scene examination.
Anyone with information is asked to call the Northland Police on 09 430 4520.