Mobile operator O2 has issued an apology to more than 450 customers who had their personal email addresses disclosed in a general message circulated last week.

On Wednesday evening, O2 sent an email to customers who had signed up to be notified when the next batch of 32 gigabyte iPhones would be in stock the next day.

However, the sender failed to send the email as a blind circular with the result that anyone who received the email could also see the personal email addresses of all 457 people on the list.

Although the email was recalled almost immediately, the incident is a breach of Section 2 of the Data Protection Act. A spokesman for 02 said that the incident was the result of an "administrative error".