Three Mobile recently admitted that hackers had hacked customer upgrade database after using an employee log in. Three Mobile confirmed the breach but declined to say whether customers’ data was stolen or how many have been affected. It mentioned that the data accessed included names, phone numbers, addresses and dates of birth, but added that it did not include financial information.

It comes after Talk Talk, the phone and broadband company, admitted in October last year that the private details of 1,57,000 customers had been hacked.

The investigation is ongoing and the company is taking steps to further strengthen our controls. Three has over nine million customers and it is understood that hackers, who used company access codes to get into the system, had access to large parts of the upgrade database.