A shipment of 613 kilograms of the drug - with what police say is a retail value of more than $245 million - was stopped at Auckland Airport last Thursday.
Six people aged between 27 and 36 have been arrested and some have links to the Comancheros motorcycle gang.
Investigators made further enquiries into the intercepted shipment over recent days and search warrants were executed across South Auckland yesterday.
Those arrested face serious drugs charges in the Manukau District Court relating to the importation and supply of methamphetamine, along with money laundering offences.
Police Commissioner Andrew Coster said the National Organised Crime Group had been investigating a criminal syndicate's alleged involvement in importing controlled Class A drugs into New Zealand.
The interception of methamphetamine was the largest ever at New Zealand's border, Coster said.
"This seizure of more than half a tonne is a significant result by our National Organised Crime Group to combat the harm methamphetamine causes to our communities. Had this shipment been distributed across New Zealand it would have caused immense harm to the vulnerable communities these criminal groups were preying upon.
"Police estimate this seizure would have caused more than half a billion dollars' worth of social harm, according to drug harm index figures."
The operation - dubbed "Weirton" continued, Coster said.
Police could not rule out identifying further individuals involved and further charges being laid as a result.
Both Coster and Customs Intelligence, Investigations and Enforcement group manager Dana McDonald said the agencies working together had contributed to the result.
Photo: Supplied / NZ Police Caption: Police Commissioner Andrew Coster said the interception of methamphetamine was the largest ever at New Zealand's border.