Cyberattackers may have pilfered the data of 90,000 Bank of Montreal (BMO) and Canadian Imperial Bank of Commerce (CIBC) customers. Both banks were contacted by cybercriminals, purporting to have stolen customer data.

According to Reuters, hackers told Bank of Montreal that they had stolen the personal and financial information of a chunk of the bank’s customers–estimated by the bank to be up to about 50,000. CIBC was told by hackers that data pertaining to 40,000 customers of its Simplii Financial subsidiary had been compromised.

That claim, reports Canadian Broadcasting Corporation (CBC) News, “appeared to be confirmed in a letter to the media from someone who said they were demanding a $1-million ransom from the banks.” The ransom letter included a sample customer record. When the alleged victim was contacted by CBC, she verified that the information  in the letter was accurate.

“Bank of Montreal said it believed the attack originated from outside the country and was confident the exposures that led to the theft of customer data had been closed off,” reports Reuters. CIBC has not yet confirmed if, in fact, it was breached, “but is taking the claim seriously.”

Get the full story at Reuters.