Two men have been arrested in Christchurch after 49 kilograms of methamphetamine - worth $50 million - was smuggled into the country in a shipment of safety lights.
The arrests were made after a joint police and Customs operation over the past two weeks.
Police said the drugs arrived into Christchurch in an airfreight consignment from Mexico on 1 November.
The drugs were hidden in a shipment of safety lights in 40 separate packages weighing 1-1.2kg each.
Police said the exact weight of the product was still to be determined, but said it was the largest-ever seizure of methamphetamine in the South Island.
The drugs had a potential street value of $50 million.
Two Christchurch men - aged 25 and 31 - were arrested after several search warrants were carried out in Christchurch and Auckland.
They appeared in Christchurch District Court today on charges of importing a Class A drug, and possession of methamphetamine for supply.
They have both been remanded in custody to reappear later this month.
Detective Inspector Corrie Parnell said it was a significant result for police and Customs.
"These drugs, should they have made it to the streets, would have caused significant harm to people and communities, not just in Canterbury, but across the country."
Customs spokesperson Joe Cannon said the seizure was the result of risk-profiling and targeting work that Customs carried out for all goods, people and craft coming into New Zealand.
"We maintain a national perspective to protect our border, and will do everything possible to keep this hideous drug away from our communities."