The operation — dubbed Operation Brewer — resulted in almost 200kg of methamphetamine seized by Customs at the Ports of Auckland.
The police said the drugs were hidden in four wheat thresher machines that had been imported from Dubai.
Detective Inspector Tom Gollan said it was a "sophisticated concealment method".
"Police believe this haul of methamphetamine was destined for the New Zealand market and if it had not been intercepted it would have resulted in more than $200million worth of social harm caused across a lot of very vulnerable communities."
Four men were arrested in July while dismantling the machines on a rural south Auckland property.
Two others were also arrested in the following days.
All six have appeared in court, facing charges of importing and possessing methamphetamine and participating in an organised crime group.
All have pleaded not guilty.
The three people are accused of organising and facilitating the drug import were due to appear in court again yesterday.
