Six people have been arrested and $2m worth of assets have been seized following a police operation against organised crime in Hawke's Bay.

The National Organised Crime Group and Eastern District Police executed multiple search warrants across Hawke's Bay as part of 'Operation Dusk' - an 18 month investigation targeting senior members of the Mongrel Mob across Hawke's Bay.

Additional search warrants executed over the past three days have targeted other organised crime groups including members of the Black Power and Outlaws MC.

Eastern District Police detective inspector Rob Jones said approximately $2m in assets, 14 firearms including military style semi-automatic weapons and pistols, ammunition and large quantities of cash were recovered.

Illicit drugs including methamphetamine, cannabis and synthetics were also seized, as well as 15 motor vehicles, including a 2020 Range Rover, high-end classic cars, two trucks, four Harley Davidson motorbikes, a dirt bike, jewellery, a boat, two jet skis, trailers and a digger.

Five residential addresses have been restrained pursuant to the Criminal Proceeds (Recovery) Act 2009, while two businesses are being assessed for their links to organised crime.

National Organised Crime Group detective inspector Darryl Sweeney said police have arrested six individuals - three men and three women - of a range of ages.

"They are facing serious drugs and firearms charges," he said. "They will be appearing in court in due course.

"Police are absolutely committed to disrupting, deterring and dismantling organised crime networks throughout regions including Hawke's Bay and those that support these criminal business entities.

"This should serve as a clear message that the National Organised Crime Group will continue to work across New Zealand to hold gang members to account."

Sweeney said as the operation is ongoing, police are not ruling out further arrests, restraints or charges.

The Hawke's Bay Police Community Teams continue to liaise with communities affected by gang activity, providing reassurance and support.