Hackers have stolen the personal data of 1.3 million customers from the French branch of mobile network operator and internet service provider Orange.
The hackers have access to names, email addresses and phone numbers.
Orange France has been aware of the hack since 18 April but delayed announcements to assess the damage.
Earlier this year, Orange saw the personal data of 800,000 of its clients stolen in a similar attack.
“For the people concerned, the data recovered includes their first names and surnames,” an Orange representative said. “In addition, depending on the information supplied, email addresses, mobile and fixed-line phone numbers, the identity of the person’s internet operator and their date of birth, were also recovered.”
Orange was not able to say whether the stolen data was encrypted, although the company has warned customers that the theft could be used to contact those concerned by email, SMS or phone, particularly for phishing purposes.
Customers have expressed their anger at the situation on the company’s Facebook page and across Twitter.
An Orange representative said: “All necessary actions have been implemented to correct the relevant technical dysfunctions and to prevent any new illegitimate access to this data.”