The DOJ Web site was made inoperable by a cyberattack on Thursday according to officials, just hours after the Justice Department shut down megaupload.com and indicted several employees. As Ed O’Keefe and Ian Shapira reported:

Portions of the Justice Department Web site became inoperable Thursday just hours after federal officials seized and shut down the file-sharing Web site Megaupload.com and arrested several of its executives on charges of violating piracy laws.

Anonymous, a group of Internet hackers, claimed responsibility for the attack via Twitter, as it usually does.

Barrett Brown, the Dallas-based founder of an online think tank that works with Anonymous, confirmed in a phone interview that Anonymous took down the Web sites using “distributed denial of service” attacks — essentially bombarding the sites with an overwhelming amount of traffic.

Several attempts to load the site, www.Justice.gov, failed late Thursday afternoon.

In a statement, the Justice Department said late Thursday that the site was “experiencing a significant increase in activity, resulting in a degradation in service. 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.”

A Twitter feed published by Anonymous members said the group had also attacked UniversalMusic.com and the Web sites of the Recording Industry Association of America and the Motion Picture Association of America.

Officials claim megaupload.com was running an international criminal operation that allowed users to illegally access movies and music which they did not own. As Sari Horowitz and Cecilia Kang explained :

Federal authorities shut down one of the Web’s most popular sites Thursday on charges that it illegally shared movies, television shows and e-books, prompting hackers to retaliate by blocking access to several Web sites, including those of the Justice Department and Universal Music.

The shutdown of Megaupload was part of a federal indictment accusing the company of running an international criminal organization that allowed consumers to easily watch or share pirated content. The site’s offerings were a virtual bazaar of what the Internet has to offer, including pornography and illegally copied video games, federal officials said. In some cases, people could see movies before they were released in theaters.

Investigators say Megaupload’s executives made more than $175 million through subscription fees and online ads while robbing authors, movie producers, musicians and other copyright holders of more than $500 million.

“This action is among the largest criminal copyright cases ever brought by the United States,” the Justice Department and FBI said in a statement.

Seven executives, including Megaupload’s founder, were indicted. But Swizz Beatz, who is listed on some sites as the company’s chief executive, was not charged. Beatz, a musician, is married to singer Alicia Keys. Although the music and movie industries are among those most harmed by piracy, numerous celebrities have endorsed the Megaupload site, including Kanye West, Kim Kardashian, and rappers P. Diddy and Will.i.am.

Megaupload was estimated at one point to be the 13th most frequently visited site on the Internet, according to the indictment. The site claims to have about 50 million daily visits.

Megaupload.com has several celebrity backers, including musicians like Swizz Beatz, who is its CEO, and supporters who include P. Diddy and Will.i.am. As Cecilia Kang reported:

Megaupload, the file-sharing Web site shut down by federal law enforcement on Thursday, has some big celebrity names behind it.

Its chief executive, Kaseem “Swizz Beatz” Dean, is married to R&B and Hip Hop star Alicia Keys. He also counts powerful artists including P. Diddy and Will.i.am. as friends.

Check out his resume on Billboard.

That comes in handy when trying to promote your Web site, which the FBI said has been the 13th most visiting site on the Internet.

Check out this video endorsement by Jamie Smith, Kanye West and other celebrity friends of what federal law enforcement says breaks copyright laws. Its founder, Kim Dotcom, and several company executives were charged with violating piracy laws, the Associated Press reported.

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