Nationwide Building Societyhas only just informed customers that sensitive data they entrusted to the institution's care may have been stolen when an employee's laptop was taken in a domestic break-in a number of months ago.
But the institution is adamant that account holders' money is safe as it hasn't seen any evidence of fraudulent activity resulting from the burglary.
Despite knowing about the theft since August, the building society waited until Saturday to tell its 11 million-strong customer base.
It says the reason for the delay in announcing the theft was because it "did not wish to create undue anxiety amongst our customers" and was advised by experts not to go public in case the news comprised security.
In addition, the organisation says it has taken additional steps to protect customers and enhance security measures, in addition to writing to account holders and posting a set of frequently asked questions (FAQs) on its site.
"...The laptop contained some customer information to be used mainly for marketing purposes," said Nationwide's chief executive Philip Williamson in an alert posted on the company's website.
"The information did not include any PINs, passwords, account balance information or memorable data and I can reassure you that there has been no loss of money from our customers' accounts as a result of this incident."
He added: "Not only am I sorry for any concern this incident may have caused but may I also confirm that all Nationwide customers are covered by the society's customer promise that 'If you are the innocent victim of fraud, you will not lose out.'"
