Updated: Hacker group Anonymous claims responsibility for shuttering Justice.gov

Thursday - 1/19/2012, 8:07pm EST

Hacker collective Anonymous has claimed responsibility for taking down the Justice Department's website just hours after Justice officials shut down a popular file-sharing website.

The loose group of activist hackers — or hactivists — claimed responsibility via several of the group's Twitter accounts.

As of Thursday evening, the group had also claimed responsibility for shutting down the websites belonging to the Motion Picture Association of America, the Recording Industry Association of America and Universal Music.

"The Department of Justice web server hosting Justice.gov is currently experiencing a significant increase in activity, resulting in a degradation in service," a DoJ spokesperson said in an email. Thursday evening "The department is working to ensure the website is available while we investigate the origins of this activity, which is being treated as a malicious act until we can fully identify the root cause of the disruption."

Megaupload, one of the world's largest file-sharing sites, was shut down Thursday and its founder and several company executives were charged with violating piracy laws.

"Anonymous has been creating issues across the Internet for some time," said Van Hitch, former DoJ chief information officer. "Also, denial of service attacks are not new to DOJ or other government agencies. The key is figuring out the how's and where's of this attack and responding to it."

Hitch retired in July after spending nearly nine years as Justice's CIO.

The arrests occurred just one day after websites including Wikipedia and Craigslist shut down in protest of two congressional proposals intended to thwart online piracy.

(The Associated Press contributed to this report)