Police are still looking for a variety of weapons in relation to a spate of recent drive-by shootings, Police Commissioner Andrew Coster says.
Rising tension between the Tribesmen gang and its former feeder gang the Killer Beez was linked to a number of shootings in Auckland last week, with seven shooting incidents across the city on one night.
Coster told RNZ Checkpoint there had also been a range of what he described as lower-level incidents but would not go into detail.
"The tensions have been high, the issue here is how they behave and what we're doing there is focusing on the members on these groups, whether it's search warrants, whether it's any avenue we can find to put pressure on and make it clear they need to pull their heads in," Coster said.
"We cannot sustain this kind of violence in our communities and police is cracking down on these two groups, sending a clear message about the way they need to behave."
There were a range of theories about why the tension had flared but he could not say the intelligence he had was 100 per cent accurate.
"I have no reason to believe this relates to drugs, I believe it relates to long-running tensions, probably at a personal level between these groups, but I'm not going to go into detail because I only have rumour and speculation on that front.
"I can tell you no reason justifies the kind of violence that we have seen in our communities."
At the weekend police said they had recovered four guns and 250 rounds of ammunition following last week's shootings.
"The weapons we've recovered are varied, we've recovered ... four firearms, two of those were restricted firearms, we are very concerned about their access to firearms."
The recovered firearms were not automatic weapons but high-powered weapons, he said.
"We're looking for a variety of weapons that would include shotguns and rifles. We have recovered some but we have no doubt there are more to be found. We are dealing with the consequence of decades here of lax gun control and we have a lot of work to do."
This year's Budget set aside $208m over four years to establish a new Firearms Business Unit within police to oversee the register and other ongoing Arms Act legislative changes.
Police now had the legislation and funding to put in place firearms regulation that would make the community safe, he said.
"It's going to take some time for that to have the effect, in the meantime we invite anyone who has information about firearms that are illegally held to come forward so that we can get those firearms back."
Coster said police had direct contact with the leaders from both gangs and had made efforts at bringing about a resolution.