An investigation by the information commissioner has been launched, after The Times revealed that the bank account details, including PINs and security codes, of thousands of people are for sale online.

The paper found more than 100 websites selling the account details of British customers. It also found one site offering 30,000 British credit card numbers for less than £1 each and another offering to sell a British e-passport.

The Times was able to download the bank account details of 32 people, including a High Court deputy judge and a managing director, for free. The details were offered as “tasters” by illegal websites, the paper reported, as a way of inducing people to pay to download more information.

The information commissioner, Richard Thomas, is now investigating the breach. Thomas will be addressing the Commons Justice Committee today, to argue for greater penalties to be imposed on organisations that fail to protect data adequately.