New rules have come into force on so-called military style weapons.
The restrictions mean some weapons will have import controls while others will only be legal for people with special gun licences.
The Arms (Military Style Semi-automatic Firearms and Import Controls) Amendment Act was passed in 2012 but came into effect today.
It creates a new category of airgun - the restricted airgun. A restricted airgun is an airgun (with or without any of its attachments) that either has the appearance of being a pistol, restricted weapon, or military style semi-automatic firearm or is designed for use in airsoft or paintball sports and has the appearance of being a firearm capable of full automatic fire.
From today, anyone importing restricted airguns will require an import permit from police.
Police will need to be satisfied that there are special reasons for allowing the airguns to be imported into New Zealand before they issue a permit.
Police welcome law
Inspector Joe Green, Police Manager for Arms Control, said police welcomed the amendment.
"Police have attended many incidents where these so-called 'toys' have been used to commit violent crime, or have been used to intimidate people, sometimes causing serious injury," he said.
New restrictions will also be imposed on semi automatic weapons and shotguns used for hunting. If they have a pistol grip, owners will be required to hold a licence for military style weapons.
However, recreational firearm users say there is still a lack of awareness about the changes.
"There is some concern about the process and how it was done and also what that means for the individual," said Pistol NZ President Debbie Wakker.
Gun owners have until six months to make changes.
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