"The attack lasted for a few minutes and was successfully tackled by the bank's security systems. The only thing that was affected by the denial-of-service attack was our website," the official said, declining to be named.
Anonymous originated in 2003, adopting the Guy Fawkes mask as their symbol for online hacking. The mask is a stylised portrayal of an oversized smile, red cheeks and a wide moustache upturned at both ends.
"Olympus will fall. A few days ago we declared the revival of operation Icarus. Today we have continuously taken down the website of the Bank of Greece," the group says in a video on You Tube.
"This marks the start of a 30-day campaign against central bank sites across the world."
© Thomson Reuters 2016
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