An indoor cannabis operation run by a refugee and involving thousands of dollars of stolen electricity was uncovered after a series of anonymous letters were sent to police.
Van Huy Bui, 34, was convicted of multiple charges of cultivating and selling cannabis, possession of methamphetamine and theft in the Auckland District Court last week.
Bui came to New Zealand from Vietnam as a refugee and was granted residency, the New Zealand Herald reports.
He had been deported from Canada in 2005 for setting up a similar drug-growing operation.
Bui and co-accused Binh Van Le were arrested by New Zealand police in 2008 after authorities received anonymous handwritten letters about a cannabis operation at a Glenfield house.
Police executed a search warrant and found both men at the house, which had been "heavily modified" and had "crude coverings" over its windows.
It was fitted with lights, fans, filters and irrigation equipment, and police found more than 220 cannabis plants and 11.1kg of dried cannabis.
Police contacted the property's owner, who revealed Le also rented another of their houses, in Browns Bay.
There, police found a similar growing operation, with more than 230 plants and 700g of dried cannabis.
Underneath both houses were circuit breakers and timing devices connected to unmetered power cables to help avoid the high power costs of running the operations, which would likely have drawn the attention of power companies.
It is estimated the pair illegally obtained $11,000 worth of electricity from Meridian Energy at the first house, and $15,000 from Mercury Energy at the second.