U.S. and Canadian authorities have revealed details for the first time about a smuggling ring that used a remote portion of the international border to move more than 1,000 kilograms of cocaine into Canada and 1.3 million tablets of the designer drug ecstasy back into the United States over more than two years.

Michael Cotter, the U.S. Attorney for Montana, revealed details of the operation for the first time Monday, after U.S. District Judge Sam Haddon sentenced one of the ring's Canadian drivers to five years in prison.

Cotter said the joint investigation resulted in one of the largest drug busts seen on either side of the border, with authorities seizing 414 kilograms of cocaine and 29 kilograms of ecstasy, and arresting 17 people in the U.S. and in Canada.

"This is certainly the largest seizure both here in Montana and Saskatchewan," Cotter said at a press conference in Great Falls.

Cotter and officials from the Royal Canadian Mounted Police, the Department of Homeland Security, the Drug Enforcement Agency and the Border Patrol described how from 2009 until last fall, the ring would use rental vehicles to transport cocaine from southern California to small border outposts in Montana.

The cocaine would then be delivered across the border and driven to British Columbia for distribution.

The suspects also hid ecstasy and marijuana from British Columbia in vehicles that would head south into the United States for distribution.

Cotter said the estimated street value of the drugs seized is $17.5 million.

Aaron Heitke, deputy chief of the Border Patrol in Montana, said authorities first became aware of the ring after an arrest was made at a border post last year.

Alleged ringleader from B.C.

Inspector Mercer Armstrong, the officer in charge of the RCMP F Division in Saskatchewan, said the alleged ringleader is Brock Palfrey of Silverstar, B.C.

He said Palfrey is awaiting trial in Canada on charges of importing cocaine into Canada, possession with intent to distribute and criminal organization. Two other alleged co-conspirators are awaiting trial in Canada and a third has negotiated a plea deal.

Two Canadian men have been sentenced in Montana after negotiating plea deals.

On Monday, Haddon sentenced Christopher Chambers to five years in prison after Chambers pleaded guilty to conspiracy to export cocaine.

Chambers drove a scout car that accompanied the rental cars carrying drugs from California to the border.

Haddon gave Chambers a lower sentence than federal guidelines recommend after Chambers pleaded guilty to conspiracy to export cocaine.

The judge said he factored in that Chambers had not been in trouble before and also the support shown by the 30 friends and family members from Canada who were in the courtroom.

A contrite Chambers pledged to be a "better son, a better husband and a better man."

"My actions in this conspiracy were inexcusable and very immature," he told the judge.

Haddon previously sentenced another Canadian, Gregory German, to 7 1/2 years in prison for his role in the drug smuggling ring.

Authorities said more arrests could follow.

Cotter and Armstrong said the investigation shows the need for interagency co-operation to control illicit drug smuggling through the remote 941-kilometre-long border between Montana and Canada.

"I certainly wouldn't want to say that it's the beginning of an epidemic, but certainly the nature of our border makes for the possibility for criminal organizations to look at that border area to be able to carry out the goals that they have," Armstrong said.