Six carved items made from rhinoceros horn have been seized in Auckland, the first time rhino horn has been seized in New Zealand.

The items were found during searches of addresses in Auckland's Glenfield and Epsom, in a joint operation between the Department of Conservation (DOC), Customs and Police.

The horn had been carved into small bowls, a piece of jewellery and an ornament, and had a combined weight of 1.73kg.

"We believe these items – although relatively small - would fetch very high prices on the international black market," said Dylan Swain, lead officer of DOC's investigations team.

"Their prices would range from $15,000 to several hundred thousand dollars."

The agencies believe the horn had entered the country without a permit years ago, and had been traded illegally in community markets across Auckland since then.

And two members of the public are "helping DOC with its enquiries into the trade of the rhino horn items," the agencies said.

Importing rhino horn without a permit can be penalised with up to five years in prison, or a fine of up to $100,000.

Customs investigations manager Cam Moore praised the cross-agency collaboration that went into the seizure.

"Customs is committed to enforcing cross-border wildlife crime and protecting our own flora and fauna from being exploited.

"This is a great result for all agencies involved," he said.