Virgin Media has lost an unencrypted computer disc containing bank details, names and addresses of some 3,000 UK customers that signed up to its services via Carphone Warehouse stores from January.

It is understood that the group is communicating the data leakage - which occurred in late May - individually to the customers affected and is currently carrying out a review of its data protection policies and practices.

"We have been working with the Information Commissioners' Office on this matter and will ensure we meet our responsibilities and fully support our customers through this process," Virgin Media said in a statement.

It is not know why the records were stored in a CD, as the business’ standard procedure is to use secure FTP transfers.

Virgin’s case follows last week’s news of the online hack of clothing business Cotton Traders, which lost details belonging to up to 38,000 customers.