Four men have been charged with more than 64 crimes, including robbery, armed sexual assault, breaking and entering, use of a firearm and more.
Clayton Roach, 38, Vincent Parent-Lévesque, 23, Yossi Avadov, 23, and James Craigwell, 43, were arrested April 15, after days of police surveillance.
Police say the charges are in connection with 14 violent crimes committed since the beginning of March.
Three homes and two vehicles were searched, and police seized firearms, baseball bats, hoods, cayenne pepper, cell phones and cash.
Police allege the men are responsible for robbing homes, convenience stores and bars in the Montreal boroughs of Lachine, LaSalle, Verdun and the Southwest, as well as the cities of Laval, Sainte-Thérèse, Terrebonne, Saint-Adèle and Saint-Sauveur.
"They're very serious criminals. They're ready to rob people, they're ready to use guns. They're very violent," Mustaky Jean, commander of the the Montreal police service's southern division, told CBC.
Jean said all four have criminal records for violent crimes and drug offences. He said one previously served a 19-year sentence for murder.
Police tailed 1 suspect
Jean said investigators had surveillance video and witness accounts of the robberies, but it was difficult to identify the suspects because they always wore masks.
The police got a break in the case came when they were able to connect a vehicle to one of the suspects. Investigators started tailing him, which led them to the three other suspects.
All four were then placed under 24-hour surveillance.
Jean said last Friday, as the men were preparing to rob a house in Lachine, the police tactical team swooped in and picked them up.
Jean said investigators believe the four may be responsible for dozens of other crimes in the greater Montreal area. They're asking anyone who thinks they may have been a victim of the suspects to get in touch.
The four men remain in police custody.