Police in Auckland have taken over $58 million out of the hands of organised crime, with more than 10 tonnes of cannabis destroyed in a sweeping set of operations.
Over a month, Police have shut down 120 cannabis grow houses nestled amongst suburban and rural communities.
So much cannabis was destroyed, four trucks were required a week to cart away cannabis discovered in Waitematā district alone.
They were largely hidden in plain sight, in average-looking rental properties in areas like Pōkeno in the south, Pakuranga in the east, Henderson in the west and Torbay to the north.
Police made 30 arrests, most of which were Vietnamese nationals who are going through the deportation process.
The numbers speak volumes themselves: 128 addresses searched, over $12,000 in cash and more than 11,000 plants destroyed.
Operation Beryl saw Waitematā Police carry out a two-week sting with an almost 100 per cent strike rate on properties searched.
More than 9 tonnes was located there alone.
"Police efforts have dealt a significant blow to the pockets of organised crime figures and their associates, denying them a payday of more than $50m," Detective Inspector Callum McNeill says.
"This is not just a small group of cannabis plants located but instead would have gone on to fund a range of organised criminal activities in our communities."
Police operations were carried out between late July and through August.
Operations were also carried out in Auckland City and Counties Manukau districts, targeting cannabis grow houses.
More than half a tonne of cannabis was located by Auckland City Police at a warehouse in the Penrose area.
And further south, Counties Manukau Police destroyed more than 140 kilograms of cannabis and 4,200 plants.
Cannabis grow houses linked to Vietnamese organised criminal operations have increasingly come to Police attention in recent years, Detective Inspector McNeill says.
According to Police records, 97 cannabis grow houses were located by Police in the Auckland region in 2024.
In the first six months of this year, to 30 June 2025, Police had already located 90.
Detective Inspector McNeill says growing cannabis is not the only illegal activity taking place.
"We know these rental properties are often fitted out with shoddy electrical wiring, fuelled by stolen power which is diverted from other properties.
"It's not only illegal but poses very real dangers to those operating the grow houses and innocent members of the community."
In many instances, Police have been called to residential house fires after evidence of a cannabis grow operation is discovered.
• Police to landlords: Listen up
Police are working closely across the sector around targeting and preventing these operations from getting off the ground.
But at the same time, Detective Inspector McNeill says landlords need to pay attention or risk insurance not paying out.
"Landlords, need to remember they have obligations to carry out due diligence on prospective tenants.
"If tenants move in and turn your house into a growing operation, you risk being liable in the event of a fire or significant damage.
"It's unfortunate that we are finding in many cases private landlords are not carrying out basic checks before or during tenancies."
Police recommend landlords to carry out checks before signing up tenants:
- Carry out reference checks.
- Meet tenants face-to-face and check IDs
- Credit and income verifications.
Always ensure you carry out regular inspections of your properties.
"Be aware if tenants have a preference to pay rent in cash or offer to pay more to avoid inspections," Detective Inspector McNeill says.
Landlords and neighbours can also play a part in stamping out these operations.
"By working together, we can all keep our communities safe."
You can report suspicions of an address to Police via 105 or Crime Stoppers anonymously on 0800 555 111.
"We also advise people that if they come across a cannabis grow house not to enter or touch any equipment, instead alert authorities so the area can be made safe."