New figures show New Zealand's gang problem is growing, with 1500 more people joining the ranks in the last two years.
In April 2018 there were 5785 identified gang members and prospects, according to data released to RNZ.
The largest gang is the Mongrel Mob, while Black Power is the second largest.
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Just under a third of prisoners are gang members, and 7000 Kiwi children live in gang-connected families.
The Gang Intelligence Centre tracks the numbers and says some of the change might be due to better information gathering. However the effect gang members have on New Zealand is significant.
"It's not just the gangs themselves - it has a huge effect on family, a huge effect on community and New Zealand as a whole," centre manager Cathy Toi-Cassidy told RNZ.
"It's probably bigger than people realise."
Canterbury University criminologist and sociologist Professor Greg Newbold told RadioLIVE in February there are different categories of gangs.
The Mongrel Mob and Black Power are larger and more amorphous, and motorcycle gangs such as the Comancheros and the Hell's Angels are smaller and better organised.
Many of the younger members are joining gangs to make money from drug dealing.
"You still have your traditional gangs and the traditional gang lifestyle... but there's no doubt that New Zealand gangs are throughout the whole of the New Zealand drug market," Ms Toi-Cassidy told RNZ.
And it's not just our gangs causing problems. Australian gangs are gaining a foothold here, aided by Australia's policy of deporting Kiwi-born Aussies.
The Australian Rebels and Banditos gangs have been making big money from the drug trade in New Zealand for years, and now their notorious rivals - the Comancheros - are setting up shop.
The gang is using social media to let people know they've crossed the ditch into New Zealand. Experts warn that these Comancheros members are like nothing we've seen before and the gang is considered the most dangerous in Australia.
Queensland University of Technology law professor Mark Lauchs told The Project in March that gangs like the Comacheros are known for frequent use of firearms and "public displays of random violence".
"They're absolutely trying to recruit... once they're in the club, they're in a culture that promotes and excuses violence."
He said there's "guaranteed to be a war" as more rival gangs arrive in New Zealand.
However Mr Newbold says that fear of gangs among the public is overblown.
"I don't think that gangs intimidate anyone except each other. They intimidate people who deal drugs and they intimidate people who buy drugs off them, and they intimidate people who rip them off or fall out with them," he says.
"They can be intimidating to other criminals, but to the average person on the street - to you and me - I don't think we've got anything to fear from the gangs at all."