Tensions have been building between Rotorua Black Power and Mongrel Mob members.
Gang tensions in Rotorua are rising, with three incidents in three days including one involving bats and bars and another in which gang members allegedly stole rival patches, police say.
But they say they are putting "the hammer down" and will not stop until people are held to account.
Rotorua police have impounded one vehicle and arrested six people so far - five Black Power members and one Mongrel Mob member - in relation to the spate of violence.
It followed clashes between the Tribesmen and its former feeder gang the Killer Beez that were linked to a number of shootings in Auckland last week, with seven incidents reported across the city in just one night.
Tensions between gangs in Rotorua had been rising for two weeks and had "really come to the fore" in the last week, police Rotorua area commander Inspector Phil Taikato said.
Taikato said it was not believed to be linked to what was happening in Auckland and the public was safe, given the violence was gang on gang.
He said more Mongrel Mob members from the East Coast, King Country and Te Kaha were in Rotorua, with some said to have gone to emergency housing with their partners.
The first reported gang-related incident was last Wednesday at around 3pm on Sequoia Cres, when a few carloads of Black Power members allegedly attacked two Mongrel Mob members from out of town, and stole their patches.
Police have helped return one of the patches.
Taikato said police believed this was in retaliation to an earlier unreported attack on two Black Power members.
On Saturday, an alleged incident between members of the rival gangs broke out at the Kawaha Point Liquor Store at about 4pm and weapons such as baseball bats and bars were allegedly used.
There was also an alleged stabbing on Saturday at around 3.45pm in an internal conflict between two Mongrel Mob members on Susan St.
There was also anecdotal information about shots fired on separate occasions, but police were yet to find evidence.
Taikato said charges had been laid including wounding with intent to cause grievous bodily harm, aggravated robbery and driving offences. More arrests were expected.
Taikato said most of the incidents were "random" and "cowardly" and he did not expect the violence to escalate.
He said the violence was largely carried out by youths — 18-year-olds — and there were some established patched members leading the charge, but it was not believed to be part of any kind of initiation.
He said many of them had not been engaged in learning for a while and had no other hobbies or positive activities to occupy themselves.
"Social media has a lot to answer to for this. People are trying to find their fame with TikTok and Instagram, posting all of this on there."
He said there were also an unknown number of out-of-town Mongrel Mob gang members in the city from the East Coast, King Country and Te Kaha.
Taikato said their presence had disrupted the work the Gang Harm Reduction unit had been doing.
The unit, which is separate from the gang response and gang investigation teams, works with members willing to change and has had positive outcomes.
"Informal protocols" between the different factions were established through the gang harm reduction work.
Taikato said these had been working well but were breached by out-of-towners, who did not understand the protocols and saw police as the enemy.
Taikato said as much as police were prepared to work with willing gang members, "we're prepared to put the hammer down".
"All those that don't want to comply with the law, we will be arresting and we will be charging.
"We will be doing that until they're prepared to change, and that's where our gang harm reduction unit will come in."
Rotorua MP Todd McClay said members of the public, including a five-year-old, were "horrified and terrified" after witnessing recent gang fights at the weekend.
"It's only a matter of time before someone is badly hurt or worse."
He said it put the public at risk and harmed the city's reputation.
His biggest concern was around gang retaliation and growing tensions and he said police needed the tools to "break up these gangs".
"I have a huge amount of respect for policemen and women who are putting their lives at risk every day ... The Government hasn't given police the tools that they need," he said.
"When gang members know police won't pursue them because that's the policy, they act with impunity and put people at unnecessary risk."
Taikato said the response to the violence was prioritised, but police needed the public to help where they could by anonymously providing recordings, registration numbers, and identities to Crimestoppers or on 105.
University of Canterbury senior lecturer and sociologist Jarrod Gilbert, an expert on New Zealand gangs, said Black Power and the Mongrel Mob had a history of animosity spanning decades.
"There's always a risk that that can bubble over."
There were a number of things that could spark this, including personal insults, and minor or tit-for-tat incidents could "escalate very quickly".
"As soon as one side does something, the other has to respond, and they tend to respond more firmly."
He said it was key for communities to recognise that gang problems were often driven by community concerns and needed community leaders to be involved.
"The police can deal with acute problems when they arise, but the longer-term solution is community involvement."
Police Minister Poto Williams said Budget 2022 included $94 million for police to target gangs and organised crime.
This meant the Tactical Response Model, focused on keeping frontline officers safe, would be rolled out nationwide, she said.
Police also had more investigators and specialists focusing on serious and organised crime, at national and district levels.
As part of the nationwide Operation Tauwhiro, police continued to recover unlawful firearms and prevent firearm-related violence by criminal gangs and organised crime groups.
Operation Cobalt would see all police districts focus on addressing this unlawful gang behaviour.
"I know police remain committed to combating criminal activities so that our communities are safe and feel safe."
She said the Government had resourced police by $562m, which meant the service was the largest it has been. There had been an extra 125 officers deployed to the region in the last five years.
Rotorua-based Labour list MP Tāmati Coffey said the people of Rotorua have to feel safe and the Government had "rightly" invested in the force to do that.
He said the Budget investment into tackling gangs and organised crime with strong enforcement was essential, as was working with communities to address the social factors that lead people to join gangs in the first place.
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