Police have seized large amounts of contraband tobacco, drugs, cars and firearms near the city of Joliette, about 70 kilometres north of Montreal.
Sixteen people were arrested during raids on Friday. Several municipal police forces were also involved in the investigation.
According to authorities, a total of 70 cases of contraband cigarettes, approximately 700 ecstasy pills, more than 10 pounds of marijuana and more than $20,000 were seized along with two stolen trucks and six firearms.
According to Quebec provincial police, 140 officers were deployed to serve search warrants under tax laws.
Investigators searched 12 homes, 15 vehicles, a warehouse and a business.