Police have seized more than 600 cannabis plants worth hundreds of thousands of dollars in an international operation.
New Zealand investigators, working alongside Canadian authorities, discovered the plants at five homes on Auckland's North Shore.
Detective Inspector Bruce Good from the Organised Financial Crime Agency said the growers were using a very "sophisticated" set up.
"The houses were purely set up for the growing of cannabis and the people were living somewhere else," Good said.
Investigators had already seized a $7 million shipment of methamphetamine before it arrived in New Zealand.
Ten people aged between 18 and 34 have been arrested over the bust.