Hellenic Post (ELTA) said Monday it had isolated all its data center services as a preventive measure following a cyber-attack late Sunday.
It is not known if the hackers managed to gain access to the targeted networks.
Investigations by ELTA’s IT department and the cyber security experts were ongoing, while the company continued to work in collaboration with the relevant authorities, it said.
The company apologized for the inconvenience to its customers. It said intensive efforts were being made to resolve the disruption.