INVESTIGATION: Police seen at the Lyttelton Port Company's container depot in Woolston.

Cocaine worth up to $1 million was found hidden inside two suitcases brought into the country by a passenger on a flight from South America, police say.

Customs uncovered the 2.5-kilogram stash of drugs during "normal border operations" at Auckland International Airport on Friday last week, police said.

Since then, investigators say they have uncovered a cocaine supply route between Auckland and Christchurch, and arrested four Brazilian men as part of an operation dubbed Grenoble.

Detective Senior Sergeant Lloyd Schmid, from the Organised and Financial Crime Agency of New Zealand, said the cocaine seized had a street value of up to $1 million.

“Over the last five days we have undertaken enquiries to establish the intended path of the cocaine and made a number of arrests,” Schmid said. “In the process we have uncovered a supply route from Auckland to Christchurch.

“Operation Grenoble is another great example of enforcement agencies sharing intelligence, resources and expertise to combat trans-national crime,” Schmid said.

Josue Da Conceicao, 36, and Marcos Andre Barbosa, 35, a labourer, were jointly charged with the importation and possession of cocaine. Court documents listed their address as a property on Gloucester St, Christchurch.

Thiago August De Oliveira, 31, a factory hand living in Riccarton, was charged with possession of cocaine.

The trio were arrested in Christchurch yesterday in a joint police and Customs operation.

A fourth man is charged with the importation and possession of cocaine and is scheduled to appear at court in Auckland.

The accused are all originally from Brazil.

Court documents say the importation charge relates to offending on March 7.

At Christchurch District Court this morning, Conceicao stood in the dock wearing a black t-shirt. He was remanded in custody without plea while a Portuguese interpreter is arranged. He's scheduled to appear in the court again on Thursday.

Barbosa stood wearing a dirty white t-shirt with New Zealand written on the front. He was remanded in custody without plea until March 20.

Oliveira appeared wearing an All Blacks jersey. The duty solicitor told the court his client had lived in New Zealand about 18 months. He had been working at a timber company at McLeans Island for about three months.

He did not have an extensive criminal history with only a single traffic offence to his name. Information provided to the court showed he was not one of the main offenders, the lawyer said.

''His involvement came later on in the piece.''

He sought bail for Oliveira and the Crown did not oppose.

Judge Jane Farish said the accused had already ''made admissions'' in relation to ''very serious offending''.

''He's looking at a lengthy term of imprisonment so there's a real incentive for him to leave [New Zealand],'' she said.

Farish remanded him in custody without plea until Thursday when the bail application would be revisited.

SECOND COCAINE FIND IN CITY

Last month, 3 kilograms of cocaine were found in an empty shipping container by staff at the Lyttelton Port Company (LPC) city depot in Woolston.

The shipment, which had an estimated street value of more than $1 million, was not bound for New Zealand, police said.

The container was routed from South America to Europe. Police and Customs exhausted all inquiries trying to work out who was responsible for the shipment.