Three people have been arrested after search warrants were carried out at four properties in Dargaville on Tuesday.
Cannabis, methamphetamine and illegal ammunition were seized from the properties.
"A 41-year-old man and a 24-year-old female were arrested and face methamphetamine-related charges," Detective Inspector Bridget Doell said in a statement.
"A 39-year-old man was also arrested and has been charged with unlawful possession of ammunition."
Police say all three were associated with a gang and are due to appear in the Whangārei District Court on Wednesday.
"Police continue to step up enforcement and the disruption of unlawful gang activity across the country as Operation Cobalt rolls out," Det Insp Doell added.
"Our message to those involved is clear we have zero tolerance for any violence, gang and drug activities."
