Drugs with a street value of more than half a million dollars and hundreds of thousands of dollars in cash are part of a haul seized by police.
Operation Tiger, which spanned six months, was a dual-agency operation involving the Waitemata Police Tactical Crime Team and Customs.
It was specifically targeting offenders importing Class A and B drugs into New Zealand through international mail, which had been purchased on the dark net using the bitcoin currency.
The investigation was initiated after results from a previous operation in 2016 found people commonly engaging in the online purchasing of illicit drugs were often young people who did not typically have a record of previous drug offending.
Following drug interceptions at the border, Waitemata Police worked closely with Customs to identify and track down the offenders who had purchased and imported "hardcore" drugs from overseas such as methamphetamine, LSD, fentanyl and GBL.
As a result of Operation Tiger, police arrested 13 people who were charged with a total of 79 charges - the majority of which related to the importation, possession or supply of Class A and B drugs.
Eleven men and one woman - ranging from 19 to 59 years old - have since appeared in either the Waitakere, North Shore or Auckland District Courts.
Waitemata Police also seized a significant amount of cash, assets and drugs during the operation, which included:
• More than $222,000 in cash
• 1 x property
• 1 x firearm
• Various quantities of drugs were also recovered, including MDMA, cannabis, methamphetamine, LSD, GBL, cocaine and amphetamine, worth a combined total street value of more than $500,000
Detective Sergeant Tim Williams, who headed the operation, said this was a great result that came about through good collaborative work between Customs and Police.
Some drug importers were turning to the dark net due to the perception that they will avoid detection, but this was not the case, he said.
"We want drug importers to know that the risk far outweighs the gain. It is only a matter of time before Police or Customs will come knocking on your door and you will be facing serious drugs charges."
Customs Intelligence Manager Wei-Jiat Tan said the outcome should be a warning to those who seek to buy drugs off the dark net and choose to disregard consequences.
"Buyers may think small quantities of drugs don't matter and Customs won't do anything, but every seizure helps us and our partners build the intelligence picture, so it's not a matter of if they are caught, it's when.
"Even if drugs are bought under the guise of the dark web's anonymity, it is not difficult to link packages to people," he said.
"Customs and Police are actively targeting opportunists that use the dark net, and investigations such as Operation Tiger shows how small seizures are resulting in greater drug supply disruption in the communities."