Nine people have been arrested and 1586 cannabis plants seized in what police say is their largest operation targeting grow houses in the ACT.

Police searched 15 properties across the region this week, allegedly seizing about 70 kilograms of dried cannabis, $86,000 cash and six vehicles.

Seven people aged between 33 and 55 were arrested on Monday and another two, aged 34 and 44, on Tuesday. All nine have been charged with participating in a criminal group and various drug cultivation, trafficking and other offences.

Five of those arrested were unlawful non-citizens, according to police.

The operation involved police, Australian Federal Police and Australian Border Force personnel, while information uncovered during the investigation also led NSW police to a grow house in Jerrabomberra.

Detective acting Inspector Mark Battye said the operation targeted an organised crime group allegedly responsible for large-scale commercial cannabis cultivation.

“This is the largest operation on grow houses we’ve ever conducted,” he said.

Police say most of the homes allegedly used as grow houses were privately rented through online platforms without property managers.

They are urging landlords to verify identification documents and regularly inspect rental properties, with warning signs including tenants avoiding inspections, paying months of rent in advance or offering above the asking price.

Anyone with information about suspected grow houses is urged to contact police via the Crime Stoppers ACT website.

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