A four-day police operation across Northland by a team of 150 officers resulted in nine arrests and was part of an investigation into a large-scale drug syndicate.

The bust targeted the manufacture, distribution and supply of methamphetamine and other drugs in the region.

More than 150 staff, including staff from the Special Tactics Group, Auckland and Northland Armed Offenders Squads and the National Organised Crime Group executed search warrants at nine properties this week as part of Operation Nortiate, an investigation into a large drug syndicate.

Detective Inspector Rhys Johnston, Mid North Criminal Investigation Branch, said nine people were arrested, three women and six men all aged between 28 and 62.

They face a number of charges between them, including manufacture and supply of a Class A Drug, possession of methamphetamine for supply and unlawful possession of firearms.

The search warrants were carried out at various properties throughout the Northland region, including in Wheki Valley, Hukerenui, Helena Bay, Raumanga and Puwera.

Two properties in Wheki Valley were in lock down for two days from Monday as teams of police descended on the rural locations.

One property appeared to be a scrap yard with a half round hay barn and containers on site and the other was a house at the end of a track just a few hundreds metres away on the state highway.

The police activity began early Monday morning with locals in Hukerenui reporting helicopters and armed police on their rural road about 5am.

A resident of Waiotu Block Rd, Hukerenui, said he woke to hear a helicopter flying near his property. On his way to work he came across four police cars not far from his house and was approached by Armed Offender officers dressed in black kit and carrying a firearm.

Johnston said police recovered about $60,000 worth of stolen property along with drugs such heroin, cannabis and methamphetamine.

The stolen property including a flatbed truck are in the process of being returned to their rightful owners.

During the raids officers recovered two tasers and seven firearms, including a 357 Magnum Pistol, a shotgun, as well as two semi-automatic rifles now classified as prohibited under the new firearms laws.

"The drugs we located cause immeasurable harm to our communities, and families suffer as a result. We are pleased to have severely disrupted this criminal group," Johnston said.

"We are sending a message to those who choose to engage in these activities that they will be caught and held accountable."

The nine arrested are due to appear in the Whangarei and Manukau District Courts over the next couple of weeks.

Johnston said the investigation was ongoing and police could not rule out the possibility of further seizures and arrests.