Hackers stage WikiLeaks defense

LONDON – Hackers rushed to the defense of WikiLeaks on Wednesday, launching attacks on MasterCard, Visa, Swedish prosecutors, a Swiss bank and others who have acted against the site and its founder Julian Assange.

Internet “hacktivists” operating under the label “Operation Payback” claimed responsibility in a Twitter message for causing severe technological problems at the website for MasterCard, which pulled the plug on its relationship with WikiLeaks a day ago.

MasterCard acknowledged “a service disruption” involving its Secure Code system for verifying online payments, but spokesman James Issokson said consumers could still use their credit cards for secure transactions. Later, Visa’s website was inaccessible.

The online attacks are part of a wave of support for WikiLeaks that is sweeping the Internet. Twitter was choked with messages of solidarity, while the site’s Facebook page hit 1 million fans.

Late Wednesday, Operation Payback itself appeared to run into problems, as many of its sites went down. It was unclear who was behind the counterattack.

MasterCard is the latest in a string of U.S.-based companies – including Visa, Amazon.com, PayPal Inc. and EveryDNS – to cut ties to WikiLeaks in recent days amid intense U.S. government pressure. PayPal was not having problems Wednesday but the company said it faced “a dedicated denial-of-service attack” on Monday.

WikiLeaks’ extensive releases of secret U.S. diplomatic cables have embarrassed U.S. allies, angered rivals, and reopened old wounds across the world. U.S. officials in Washington say other countries have curtailed their dealings with the U.S. government because of WikiLeaks’ actions.

Neither WikiLeaks nor Assange has been charged with any offense in the U.S., but the U.S. government is investigating whether Assange can be prosecuted for espionage or other offenses. Assange has not been charged in Sweden either, but authorities there want to question him about allegations of sex crimes.

Per Hellqvist, a security specialist with the firm Symantec, said a network of web activists called Anonymous – to which Operation Payback is affiliated – appeared to be behind many of the attacks.

The website for Swedish lawyer Claes Borgstrom, who represents the two women at the center of Assange’s sex crimes case, was unreachable Wednesday.

Ironically, the microblogging site Twitter – home of much WikiLeaks support – could become the next target. Operation Payback posted a statement claiming “Twitter you’re next for censoring Wikileaks discussion.”

Some WikiLeaks supporters accuse Twitter of preventing the term “WikiLeaks” from appearing as one of its popular “trending topics.” Twitter denies censorship, saying the topics are determined by an algorithm.