Meanwhile, a British court released WikiLeaks founder Julian Assange on bail today, after several celebrities arranged payment for a 200,000-pound ($316,000) cash security payment to the court. Assange denies any wrongdoing, and his lawyers have suggested the case is part of a conspiracy to discredit WikiLeaks' work.
British authorities still say they fear U.K. government websites could be the hackers' next target. The country's national security adviser, Sir Peter Ricketts, warned civil servants this week that websites the public uses to file tax returns or claim benefits could be hit, the BBC reported.
Since WikiLeaks published a trove of secret U.S. diplomatic cables two weeks ago, Washington is believed to have pressured companies to steer clear of doing business with the anti-secrecy website. PayPal, which used to process donations to WikiLeaks, said last week that it severed the service on the U.S. State Department's request, though U.S. officials denied involvement, according to Foreign Policy magazine.
The U.S. government is also mulling how to charge Assange himself with espionage or conspiracy, searching for any evidence that he colluded with an Army intelligence analyst who allegedly stole the documents, The New York Times reported today.
Computer hackers -- some of whom described themselves as libertarian, freedom of information defenders -- have rushed to WikiLeaks' aid. They've launched denial-of-service assaults on sites like Amazon.com, the online mega-store that booted the website off its servers. A hacker group that goes by the name of Anonymous has emerged as the public face of those attacks, though members keep their own faces covered. They're infamous for attending demonstrations wearing Joker masks to disguise their identities.
One such masked "hacktivist" from the group told Sky News that their "pool of targets is actually very limited," and that because the hackers support freedom of information, they won't attack any media websites, even if they're critical of WikiLeaks or the hackers themselves.
"We are going after the agencies that were directly involved in the censorship of WikiLeaks. They include PayPal, who cut off services and withheld funds. The same with Visa and MasterCard, then Amazon, who cut off their service support," said the hacker, who identified himself as Bass.
He described one recent cyber-attack in which the group recruited 9,000 volunteers to help distribute software to inundate victim websites with information. "The software itself has been downloaded over 300,000 times," he said. He also described their attacks as deliberate, following a procedure in which possible targets are evaluated carefully.
"Someone proposes the target. We've run intelligence on them, on what we consider the pros and cons of every target and a lot of other factors involved," the hacker said.
Hackers have also announced a new campaign to disseminate the WikiLeaks cables across the Internet, asking volunteers to post excerpts of the 250,000 documents on their personal websites as insurance that the material won't be lost if WikiLeaks goes down. Calling the site a "truth-spilling platform," Anonymous announced the new operation, dubbed Leakspin, in a YouTube video earlier this week.
"We do not forgive. We do not forget," a voice said ominously.
Because of Anonymous' secretive nature, it's impossible to verify who is behind the group and whether its actions are coordinated by a single leadership.
Last week, another member of the group, who calls himself Coldblood, told the BBC that Anonymous' members are "average Internet citizens" who are motivated by injustices against WikiLeaks.