Officers initially attended the property on Montagu Street on Wednesday, after receiving a tip that a person at the address was in possession of a prohibited military-style semi-automatic firearm.

The firearm was located and secured, and Police returned yesterday about 10.40am seeking to arrest a person of interest in relation to the matter.

That person was swiftly located and arrested.

A further search of the property under the Search and Surveillance Act located an improvised explosive device (IED).

The New Zealand Defence Force Explosive Ordnance Disposal squadron was notified, and Police remained at the scene to secure it until they arrived.

While the EOD team was on site working to secure one device, another detonated, near a Police staff member.

The Police staff member was not injured but was checked over by ambulance staff.

Properties in the immediate vicinity of the address were evacuated as a precaution while the rest of the property was searched and items made secure.

Several IEDs, accelerants and ammunition were located.

Police have carried out scene examinations of the property and the offender’s vehicle, and enquiries are ongoing.

The 43-year-old man has been held in custody and is due to appear in Palmerston North District Court today on several charges, including unlawfully possessing a prohibited firearm, unlawfully possessing a prohibited magazine, and charges relating to the improvised explosive devices.

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