Police say their investigation into a methamphetamine importing syndicate in New Zealand and Canada led them to a large-scale cannabis operation.
The Organised Financial Crime Agency has helped bust the syndicate which ran cannabis-growing houses in Auckland.
The investigation began after Canadian authorities seized two shipments of methamphetamine also known as the drug 'P' destined for New Zealand and concealed in a consignment of shock absorbers.
Detective Inspector Bruce Good said inquiries led police to five houses on Auckland's North Shore rented purely to grow marijuana on a bulk scale.
Eleven people have been arrested since the operation began in December last year and $NZ90,000 in cash and and 600 cannabis plants seized.
In Canada, a person was arrested and charged in connection with two seizures which had an estimated street value of $NZ7 million.
