Three people have been arrested at Auckland International Airport in a drugs haul that netted enough of the chemical ContacNT to make P worth $4.8 million.
The three people - all from Hong Kong - are each alleged to have been carrying between four and five kilograms of the chemicalwhen they were caught at Auckland Airport at different times during the weekend.
NZ Customs Service spokesman Rowan McArthur would not say how the arrested people had concealed the chemical or how they were caught carrying it.
Mr McArthur would not provide further details because the matter was before the courts but said the three were being held in custody.
He said two Aucklanders were also arrested after a further 2kg of ContacNT was seized during interceptions at the Auckland Mail Centre, which also occurred during the weekend.
Mr McArthur said the mail centre finds were not thought to be related to the Hong Kong trio.
The pair are alleged to have hidden the chemical inside items that had been posted to New Zealand.
Mr McArthur said Customs intercepted an average of between 14kg and 20kg of ContacNT every week but 17kg was a particularly large amount to find during a weekend.
The amount seized was enough to make about 4.8kg of P, with a potential sale value of $4.8 million, he said.
Using the drug harm index, which measures factors including crime, lost output and health service use, the interceptions had avoided $1.9 million worth of harm to New Zealand.
Mr McArthur said using the mail centre was the most common way people tried to get the chemical into New Zealand.
ContacNT is a pseudo-ephedrine-based Chinese cold and flu medicine and usually arrives in New Zealand in pill form.
There have been several big seizures of the chemical in recent years.
In October last year, police and Customs found 100kg of ContacNT - enough to make 28kg or $28 million of P - in a furniture shipment from China.
