The Royal Canadian Mounted Police say they have dismantled a major drug operation importing and trafficking cocaine into the Hamilton area via Pearson International Airport.

After a six-month investigation by the RCMP, three Hamilton men and one Waterdown woman were arrested. Inspector Todd Gilmore, officer in charge of the RCMP organized crime unit, said the arrest were all made Thursday, in public "calmly and without anyone getting injured," with the help of Canada Border Services Agency (CBSA) and Hamilton Police Service.

Two of the arrested men are cousins, he said.

"It operated like a typical organized crime ring," Gilmore said. "It was processed [in Hamilton] and moved onto the streets through a series of traffickers."

RCMP seized more than five kilos of cocaine at Pearson during the investigation. But Gilmore believes more drugs made it into the country prior to the investigation beginning.

The cocaine was being imported from various South American locations by couriers, he said, who would hide the product in luggage in secret pockets or in the walls.

The product was being sold widely in the Greater Hamilton Area. Gilmore wouldn't reveal the specific locations in South America where the drugs originated. Several illegal marijuana grow operations were also dismantled as a result of this investigation.

"Activity like this is very harmful to our communities," he said. "It does not help."

A number of search warrants were executed as part of the arrests.

Gilmore is expecting to make "at least" two more arrests in the Hamilton area related to this crime ring. The four arrested are in custody and are expected in Hamilton court Friday.