Government spokesman Stelios Petsas said early Friday that the distributed denial-of-service or DDoS attack "led to the malfunction of certain websites." He said "countermeasures" had been successfully implemented, but gave no further details.
Along with the prime minister's website, targets in the attack late Thursday included the websites of the ministries of public order, interior, foreign affairs, and merchant marine, as well as the Greek Police and Fire Service.
It was the second cyberattack against government websites in less than a week. Responsibility for the first attack was claimed in an online post by a group of hackers who purported to be from Turkey. Greek officials have not commented on whether they consider that claim to be true.