Apparent WikiLeaks-related cyberattacks ramped up as thousands of people around the world volunteered their computers for use in the attacks.

Downloads of free software used in the attacks have jumped by thousands of downloads overnight to over 40,000, reported U.S. data security company Imperva Friday.

Meanwhile, the websites of police and prosecutors in the Netherlands were working only sporadically after a 16-year-old was arrested in relation to attacks on MasterCard and PayPal. Dutch media reported that the "hacktivist" group Anonymous, which supports WikiLeaks, had been targeting the two sites with denial-of-service attacks. Such attacks flood websites with traffic, making them unavailable.

Anonymous has taken responsibility for attacks on companies such as Visa that have cut off support to WikiLeaks or have been alleged to have cut off support for WikiLeaks. In Visa's case, it had begun refusing to allow donations to the site on Dec. 7, nine days after WikiLeaks began releasing classified U.S. diplomatic cables onto the internet.

A news release Friday claiming to be from Anonymous said the group wanted "to raise awareness about WikiLeaks and the underhanded methods employed by the above companies to impair WikiLeaks's ability to function."

WikiLeaks distanced itself from the attackers Thursday with this statement on its website: "This group is not affiliated with WikiLeaks. There has been no contact between any WikiLeaks staffer and anyone at Anonymous."

Toronto company hit

MasterCard, Amazon and PayPal have been targeted by attacks, along with the Toronto company EasyDNS, because of the similarity of its name to that of EveryDNS, which had previously helped translate WikiLeaks's IP address into its "wikileaks" domain name.

EveryDNS decided to stop doing that after it was attacked by hackers on the opposite side of the cyberwar — those against WikiLeaks.

Mark Jeftovic, president and CEO of EasyDNS, said word mistakenly spread that his company had revoked its support for WikiLeaks.

"And the backlash started," he said. "It was just incredible. I couldn't believe what was happening."

Since then, Jeftovic has decided to support WikiLeaks by offering its services to two domains that are distributing WikiLeaks content.

Another victim of the attacks was former U.S. Republican vice-presidential candidate Sarah Palin, whose credit card accounts were hacked after she publicly said WikiLeaks founder Julian Assange had "blood on his hands."

U.S. Attorney General Eric Holder has since said he is looking into the attacks.

David Silverberg, managing editor of the online news website digitaljournal.com, told CBC News that Anonymous, which calls its campaign Operation Payback, believes in a free and open internet.

"And they'll use anarchist methods and what they call hacktivist methods to get their point across."

Silverberg added that the attacks are being carried out by some people who voluntarily download code to harness their computers as "soldiers," along with unwitting "zombie" computers infected by malicious code.

Matt Mullenweg, founder of the online blogging service Wordpress, said he thinks retaliatory hacking is "usually kind of childish on both sides."

Meanwhile, Rob Kozinets, who researches technology and marketing at York University's Schulich School of Business, said attempts to shut down WikiLeaks are doomed to failure, but in the meantime the battle over freedom versus restriction and censorship is playing its way out on the internet.

"It's a game of whack-a-mole," he said. "As soon as you whack that mole, it's not only that another one is popping up, but another one is coming behind you to hit you on the head with a hammer."

With files from The Associated Press