So far, the group is believed to have been behind the attacks on MasterCard, Visa, Swiss payment transaction firm , PayPal, and others. All of the targets recently announced plans to terminate service for WikiLeaks after the site began releasing confidential U.S. State Department cables.

In addition to these attacks, Anonymous has also launched attackes on the Web sites of Sen. Joseph Lieberman (I-Conn.), former Alaska Gov. Sarah Palin and the Web sites of the Swedish prosecutors who are pursuing rape charges against WikiLeaks founder Julian Assange.

Jaikumar Vijayan covers data security and privacy issues, financial services security and e-voting for Computerworld. Follow Jaikumar on Twitter at or subscribe to . His e-mail address is .

in Computerworld's Cybercrime and Hacking Topic Center.