Financial details of thousands of bank customers have been lost in the post.

Bank of Scotland yesterday apologised to 62,000 customers after it confirmed that their mortgage details have been reported missing. A computer disc containing details of the mortgage accounts failed to reach the main credit reference agencies for a routine monthly update.

The bank said the disc, which was sent in the normal post with Royal Mail, has been reported as a lost item but claimed it was "almost impossible" that any financial fraud could be committed with the limited information held on the disc.

It contains the names, addresses, dates of birth and mortgage account numbers of each customer, but does not include bank account details, PINs, passwords or bank transaction information.

The bank said there was no suggestion that the disc had been stolen and that it appears to have been lost in the post.

They assured customers no-one would be left out of pocket in the "very unlikely" event of fraudulent activity on their account following the incident.

Shane O'Riordain, Bank of Scotland, group communications general manager, said: "We apologise to our customers for any inconvenience or upset this incident may have caused. We have taken immediate steps to protect our customers and make sure this does not happen again.

"We have written to all affected customers today to apologise and to reassure them that the risk of fraud is very low. In the unlikely event of any fraud, the Bank of Scotland stands behind its customers."

Royal Mail warned customers that the normal post system is not the best option available for sensitive, valuable or confidential information.