The RCMP said the group it targeted was concealing the illicit drugs by mixing cocaine with asphalt powder.
Authorities said one of the accused was considered the chemist, who they say would extract the cocaine from the mixture.
"It's a first for us," said RCMP Sgt. Luc Thibault when asked about the method.
In the past, cocaine has been hidden in ceramic tiles, but never in bags of asphalt, he said.
Police first seized about 10 kilograms of cocaine at Montreal's Trudeau Airport in 2011. But the conspiracy involved at least 70 kilograms over a 10-month period, Thibault said.
Police say the drug trafficking network was well-structured and aimed to control territory in the Montreal area as well as the Atlantic provinces.
"The investigation showed that the group dealt in large quantities of cocaine," authorities said in a statement.
Police said fifteen people were arrested Wednesday and two others remain on the lam.
Several of those accused were already incarcerated on separate charges while others were arrested by police Wednesday.
The accused face a wide range of charges that include gangsterism, importation, trafficking and possession.
Police say the arrests are part of an ongoing operation that started in 2010, looking into organized crime groups that moved in to take the place of the Mafia following Operation Colisee.
Federal authorities said Wednesday's group is linked to two other cells busted last summer. That operation resulted in 33 arrests by the RCMP.
"They were like a trio — organizations working together in order not to interfere with each other," Thibault said.
During those 2014 arrests, police intercepted more than one-million private PIN-to-PIN BlackBerry messages, evidence used to make the arrests.
Those two networks were accused of being responsible for a series of violent crimes that were committed in Montreal over more than a year.
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