Holmes said the warrants were the conclusion of an eight-month operation.
Operation Campbell, run by police's National Organised Crime Group, targeted a methamphetamine manufacturer who had established a distribution network across New Zealand.
About five kilograms of methamphetamine, three firearms and ammunition and about $100,000 and a number of other items of evidence were seized during the raids.
Holmes said the operation began on Monday afternoon and ran until yesterday morning.
"Six men and one woman, aged between 18 and 52, with reported links to the Head Hunter and King Cobra gangs, were arrested across the last two days," Holmes said.
"They face a total of 50 charges including manufacture and supply of the Class A controlled drug methamphetamine, unlawful possession of a firearm, and participating in an organised criminal group."
Those arrested will appear in Kaitaia, Auckland and Christchurch district courts.
Holmes said the investigation was headed by the National Organised Crime Group's clandestine laboratory response team and supported by local staff.
It uncovered a significant drug dealing network centred in the Northland and Auckland regions.
"Police are continuing to step up enforcement and disruption of unlawful gang activity across the country," Holmes said.
"The public will continue to see search warrants being conducted and arrests being made for identifiable offences.
"Our message to those involved is clear – we have zero tolerance for any violence, gang and drug activities.
"Methamphetamine devastates many vulnerable communities while organised criminal groups continue to profit off this type of offending.
Holmes said police were confident the operation would majorly disrupt the supply of meth.
"The combination of drugs and firearms is always a potentially lethal recipe for harm and continues to be of grave concern for police and communities.
"Police cannot rule out further arrests as the investigation is ongoing."
As the matter was now before the courts, police were not able to comment further, he said.
Three people with gang connections were also arrested in Dargaville in a separate operation on Tuesday after police executed search warrants on four properties.
Cannabis, methamphetamine and illegal ammunition were seized from the properties.