The RCMP drug squad in Montreal says a cocaine ring broken up Thursday was smuggling drugs from South America to Eastern Canada by attaching contraband below the waterline of ships.

Nineteen people were arrested in raids carried out Thursday in Montreal, Quebec City and the Saguenay, and appeared in court the same day to face several counts of conspiracy and drug trafficking.

They were targeted in two separate police investigations launched in 2004 to follow the cocaine trail.

The first ring under probe involved accomplices in Venezuela, who stuffed duffel bags with cocaine and surreptitiously fastened them to the sea-water intakes underside docked boats destined for Canada.

Divers were then dispatched to retrieve the bags once the boats were moored in Canadian waters. One such boat was nabbed in the Port of Belledune, on the south shore of the Baie des Chaleurs, in New Brunswick, where police confiscated 52 kilograms of cocaine.

The method is called "torpedoing" and underscores drug smugglers' ability to evolve with the times, explained RCMP Sgt. Maj. André Potvin.

"Since 2001, you'll understand that the criminals are a little bit more wary in using conventional ports just like the Port of Montreal and/or airports, so basically, they have to turn around to other activities, which they believe [are] not as closely monitored by police. But they're wrong."

A second smuggling ring broken up Thursday shipped cocaine from the Caribbean into Canada.

Undercover investigators with the RCMP posed as drug runners and met Colombian suppliers to arrange for a shipment, but it fell through, Potvin said. The network was shipping coke into the Maritimes and Ontario.

Police are still searching for four other suspects in that investigation.