Eight residences and a business in Laval and the North Shore were raided by police on Wednesday morning as part of an anti-drug operation.
Roughly 150 police officers took part in the operation, which targeted cocaine and methamphetamine traffickers.
The searches took place in Laval, Rosemere, Mirabel and Ste-Sophie.
Police arrested 12 people between the ages of 25 and 40, two of whom were previously known to police. They are scheduled to appear in the Laval courthouse on Thursday.
The raids were the culmination of a lengthy investigation that started in October 2017.
