Police have expressed frustration at the number of people wasting their time by submitting 'fake' notifications to hand over firearms.

Photo: RNZ / Richard Tindiller

Yesterday, Prime Minister Jacinda Ardern said the government was banning the sale of military-style semi-automatic firearms and assault rifles, as well as ammunition clips and other parts used to convert semi-automatic firearms to fully-automatic weapons.

After a reasonable period for returns, those who continue to possess these firearms will be in contravention of the law. Anyone in breach of the law will be liable to a $4000 fine or up to three years' imprisonment.

Police yesterday afternoon established an 0800 number to facilitate the collection of the weapons.

By 11am this morning, they had received 474 calls. Within one single hour, police staff had dealt with 127 calls.

Another 1000 people had used an online notification form to tell police of their intentions of handing over firearms, with a significant number of these being "fake", police said.

"Unfortunately, some people have decided it is a good use of their time to misuse the form and submit 'fake' notifications to hand in weapons," a police statement said.

"While these individuals may be short of productive work to do, police are not.

"In the current environment this is unacceptable. These vexatious forms are a huge waste of Police time and resources which could be put to better use."

The changes order the Order of Council announced yesterday would mean the listed firearms were now categorised as needing an E-class licence endorsement. Ms Ardern said it would effectively be a waste of time applying for the licence.

Police will work with New Zealand Defence Force to enable safe storage, transport and destruction of MSSAs. It will not be practicable for firearms owners to physically return their weapons to Police stations without prior approval.