Hacking collective Anonymous has declared war on the world's central banks, successfully downing the National Bank of Greece's web site in a distributed denial of service attack.
The group used YouTube to declare the revival of its 2011 campaign Operation Icarus, which was behind a spate of attacks on Wall Street banks.
The Greek central bank has confirmed the assault on its servers, which turned out the lights on its Web presence for "a few minutes" on Tuesday.
A central bank official told Reuters: "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 web site."
Anonymous says that it will extend its activities to central banks in Brazil, China, Iran, UK and USA and other regions.