Key Points:

Drugs worth $140 million were imported into New Zealand concealed in paint and plaster products in a well-planned operation, Crown prosecutors have alleged.

A depositions hearing into whether six men should stand trial over their alleged roles in a methampetamine importing ring began in Auckland District Court today.

Chen Ming Chin, 43, Deng Guo Wei, 40, Fan Li, 27, Leung Kin Kwok, 65, Pan Weifeng 35, and Zhang Yonglei, 26, were arrested after a drugs bust last year.

They face charges of importing, selling and possessing class A and class C drugs.

In May, police and customs officers seized two shipments imported from China to Auckland.

The haul included 96kg of crystal methamphetamine (known as P or ice) estimated to have a potential street value of $95 million.

Also confiscated was pseudoephedrine (the main ingredient in manufacturing P) worth $45 million.

In a summary of facts, the Crown said customs officers began Operation Major into "what appeared to be a well-organised and structured criminal enterprise" involving large scale drug importation.

After the seizures, investigators identified three further shipments in 2005 which were alleged to have contained a similar amount of the same drugs.

The Crown said the method used by the ring involved a foreign national's coming to New Zealand for about a week to set up a New Zealand company.

The drugs were then shipped concealed either as polyurethane or paint-type products along with granulated rubber compounds, or as cement-based plaster products.

Shortly before the goods were due to arrive, the foreign national would return to New Zealand and approach a customs broker to clear the goods and rent storage space.

This person would remain in New Zealand to oversee delivery to the storage unit. From there, the goods were unpacked and distributed.

The depositions hearing is expected to last two weeks.

Last September, a seventh man arrested, Fung Kai Lok, was sentenced to 15 years in jail after admitting his role at the New Zealand end of the operation.