A widespread Police operation has dealt a North Island gang a heavy blow

Police arrested 28 people with links to the Mongrel Mob Barbarians' Opotiki chapter.

Drugs, firearms, and 800-thousand-dollars of assets has been seized in searches across the Bay of Plenty and much of the North Island.

Bay of Plenty District Commander, Tim Anderson, says it's a good day for Opotiki.

He says it sends a clear message that gangs selling drugs across the Bay of Plenty will be held accountable for destructive behaviour.