Personal details of more than two million customers of Vodafone Germany have been stolen by a hacker.
Vodafone said the attacker got access to customer names, addresses, bank account numbers and birth dates.
The trove of information was stolen from a database sitting on the company's internal network.
The operator said customers had been told about the breach and warned to watch out for "phishing" messages that try to extract more personal data.
"Vodafone deeply regrets the incident and apologises to all those affected," the operator said in a statement.
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