Transcript for Hacker Group, Anonymous, Hits Federal Reserve

And, now, someone has broken into the national bank. The federal reserve. A 21st century thief breaking into files, not into metal safes. The mysterious group anonymous has struck again, with a warning, this is just the beginning. Abc's senior correspondent pierre thomas items us who these people are. Reporter: This is public face of anonymous, the shadowy group behind the hacking attack on the federal reserve. Which sets monetary policy for the u.S. Economy. This time, there will be change. Or there will be chaos. Reporter: Anonymous, a loosely affiliated network of hackers spread across the globe, and during the hack of the fed, anonymous stole the log-in credentials of 4,000 bankers at across the country. Allowing them to disrupt a key emergency communication system. Citizens of the world. We have seen the erosion of due process. The delusion of constitutional rights. Reporter: Greg house, a former member of anonymous, says expect more attacks on the government. All these big bankers and all these big rich people who have caused a lot of the problems we've had for the last few years, are not getting prosecuted. Reporter: The fbi has had some success against suspected anonymous associates. Arresting at least 20, including one man during this bust, caught on a web cam. Fbi! Get down right now! Reporter: But finding and arresting members of anonymous is challenging. For the fbi, each targeted computer network is a crime scene. You want to look for the digital footprints. You look to trace the incoming traffic that's attacking the computer and you look to see where the file was exported to. Reporter: And a big investigative tool? Fbi agents posting as hackers. In addition, the anonymous videos are also clues. The video may contain imbedded location information if the hackers do not scrub it out. And the pictures may tell investigators something about the hackers, too. An online game of cat and is under way, right now with an invisible enemy. Pierre thomas, abc news, washington.

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