Two Canadian banks on Monday reported their customer accounts may have been breached.
Bank of Montreal BMO -0.62% said some personal and financial information for fewer than 50,000 customers may have been stolen. Simplii Financial, an online-bank unit of Canadian Imperial Bank of Commerce , CM -0.84% reported that information for roughly 40,000 customers may have been stolen.
Both banks said they were contacted Sunday by “fraudsters” claiming they were in possession of the information. BMO, Canada’s fourth-largest bank by assets, said it believes the attack originated from outside of Canada.
“They appear to be related,” a BMO spokesman said in reference to the attacks, and said the claims were “unverified.”
“We are working with the relevant authorities and are conducting a thorough investigation,” the spokesman said in an emailed statement.
BMO said it is confident that “exposures identified related to customer data” have been closed off, and that it is contacting the customers who may have been affected.
Simplii said there was no indication CIBC accounts were affected. The bank said it would return any money lost from Simplii accounts to clients affected by the fraud.
Late Monday, the Royal Canadian Mounted Police said the law-enforcement agency was investigating the suspected breach, with help from affected financial institutions. A spokeswoman for the force declined further comment.
There were no signs other Canadian banks were affected.
Toronto-Dominion Bank “has not been contacted and there is no indication that our customers have been affected,” said a spokeswoman for Canada’s largest bank by assets.
Royal Bank of Canada and Bank of Nova Scotia officials didn’t immediately return calls.
—Colin Kellaher contributed to this article.
Write to Vipal Monga at firstname.lastname@example.org
Appeared in the May 29, 2018, print edition as ‘Canada Banks Report Possible Breaches.’