Two Iranian men who allegedly ran the New Zealand wing of an international drug syndicate appeared in court today after police seized $2.4 million of methamphetamine.

Yashar Ghasemi, 31, and Homayun Nouri, 42, are facing a raft of methamphetamine charges including importing the drug, supplying it, and participating in an organised criminal group.

Nouri was initially charged only with having methamphetamine for supply when arrested this week.

Police laid more serious charges after they wrapped up their operation - carrying out raids on two central Auckland addresses early yesterday morning and arresting Ghasemi.

Nouri's lawyer Mark Ryan planned to apply for bail when his client appeared in Auckland District Court via audio-video link from prison this morning, but decided against it when police laid the new charges.

He was further remanded in custody until July 6.

Ghesemi also appeared in court this morning and was remanded in custody until next Wednesday, when he was expected to apply for bail.

His family were travelling to New Zealand from Iran, the court was told.

A New Zealander with links to the King Cobras gang, David Mafi, 34, was also arrested after allegedly buying methamphetamine from the two and was charged with possession of methamphetamine for supply.

He is on bail and will reappear on June 27.

The drugs were allegedly imported by human couriers employed by the syndicate, Acting Detective Senior Sergeant Bruce Howard said.

One of the "drug mules", a 49-year-old Polish man, was intercepted with a 2kg package by Customs at Auckland International Airport and was being dealt with by the New Zealand courts.

Police also seized $16,000 in cash, a stun gun, a 2007 Range Rover Sport, a 2004 BMW car and further methamphetamine in yesterday's raids.

The arrests came after a two-month joint operation by the Auckland metro drug squad and Customs known as Operation Crow.

Mr Howard said the accused were allegedly part of a sophisticated importation operation responsible for putting large quantities of P on the streets.

"It's certainly a substantial amount of methamphetamine. It's not in the small boys play area, that's for sure. Hopefully this result might have some effect."