The Royal Canadian Mounted Police laid charges against two people who were allegedly behind cyber-attacks against three major Canadian companies in 2017 and 2018.

The charges stem from online security breaches reported by Canadian Tire Corp., the Bank of Montreal and Simplii Financial, a unit of the Canadian Imperial Bank of Commerce, where tens of thousands of customers had their personal and account information electronically stolen. 

At the time, unnamed hackers threatened to make the stolen customer data public and the banks said they were working with authorities on the incident.

"If it had not been for the valuable collaboration of these three companies, we would not have been able to bring these two individuals to justice. These partnerships are key in solving these types of crimes, which unfortunately sometimes go unreported," said Alexandre Beaulieu, the head of the RCMP's cybercrime investigative team, in a statement on Thursday. 

The RCMP said that officers executed a search warrant at the home of the two men accused, who are brothers, in August 2018 and seized evidence that eventually allowed investigators to link the cyberattacks together. 

Jacob Costanzo-Peterson and Félix Costanzo-Peterson were charged with unauthorized use of a computer, identity theft and possession of a device to obtain unauthorized use of computers, the RCMP said. A court date has been scheduled for Nov. 5, 2020. 

The two accused previously appeared in court in January 2019 for charges related to possession of prohibited firearms and weapons trafficking after officers conducted their initial search warrant at their residence. 

Felix Costanzo-Peterson was charged under nine different sections of the Criminal Code, including two counts of identity information trafficking and two counts of unauthorized use of credit card data. Jacob faces 12 counts under four separate weapons-related charges.