The man accused of murder following the death of 49 people in the Christchurch terror attacks had a "category A" gun licence.
Prime Minister Jacinda Ardern said the man accused of murder had five guns, including two semi-automatics and a shot-gun. Ms Ardern said gun laws would change following the attack.
At present, people have to be aged 16 and older to apply for a firearms licence.
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An application is filled out and handed to police. The form requires basic personal details, place of employment, education and two referees.
Police carry out a background check to see whether the person applying is "fit and proper" to possess firearms or airguns.
The applicant receives a letter from police confirming they can undertake a firearms safety programme.
They need to study the arms code, sit the firearms theory test and take a computer-based multi-choice test.
People must pass the theory test before they can attend a firearms practical training course.
Police arrange an interview, during which they inspect the person's security arrangements. They interview referees, before deciding whether to approve the licence.
It costs $241.50 for a first-time licence holder and $126.50 for an existing licence holder to renew a licence.
Anyone can use a Category A firearm without a licence if they are under the immediate supervision of a licence holder.
A pistol can be used by anyone if they are on an incorporated pistol club range that is recognised by the Police Commissioner, and if they are under the immediate supervision of a licence holder with a B endorsement. 'Immediate supervision' means the licensed person is within reach and can control the firearm. The supervisor must not be using another firearm at the same time.
People who are visiting New Zealand for less than a year can apply for a visitor's gun licence.