A computer hard disc containing one million sets of bank details was bought on eBay for just £35.

The secondhand PC contained details of customers from American Express, NatWest and Royal Bank of Scotland. The files included names, addresses, sort codes, account numbers, credit card numbers, mobile phone numbers, mothers' maiden names and even scans of signatures - more than enough for an identity thief.

IT manager Andrew Chapman paid £35 for the secondhand machine on eBay. Chapman told The Mail on Sunday: "I couldn't believe it. In front of me was reams of extremely confidential information about thousands and thousands of people."

Although dwarfed by government data giveaways like the loss of 25m child benefit records, the data is potentially far more easily exploited by crooks.

A second computer is believed to be missing from the same site - archiving firm Graphic Data. The company said it was trying to find the second machine. ®