Police believe almost 900 people joined a gang this year, a 13 per cent increase on the year before.
Police data shows they have identified a little over 7000 people as belonging to a gang, although the number is likely higher.
Notably, a number of gangmembers with New Zealand ties have been deported from Australia. They are known as 501s, referring to the legislation underpinning the deportations.
Local chapters have sprung up of the Mongols, Bandidos and the Comancheros.
Detective Sergeant Ray Sunkel said the Australian imports were harder and brought a more violent mindset.
After arrests targeting the Mongols motorbike gang in Bay of Plenty earlier this year, community advocate and lifetime Black Power member Dennis O'Reilly said gangs like the Mongols, established by people deported from Australia, operated on an entirely different basis to the gangs New Zealanders were accustomed to seeing.
Police data shows more than 7000 people have been identified as belonging to a gang, though that number is likely to be higher. Photo / File
"They're all New Zealanders by dint of having been exported here under 501, but they're not playing the game," he said.
Police have admitted they are facing challenges in fighting organised crime and gangs.
Earlier this year, Detective Superintendent Greg Williams, of the National Organised Crime Group, told Morning Report there had been "a general arming up by the gangs" over the past three or four years, as well as a number of gangs increasing in size.
In the past year, police have sought to disrupt gangs by seizing $230 million of assets and laying money laundering charges against 118 gang members.
