The online group Anonymous hacked into the websites for the Department of Justice, RIAA, Motion Picture Association of America and Universal Music Group on Thursday, as a retaliation for the Megaupload shutdown by U.S. feds.

"The government takes down Megaupload? 15 minutes later Anonymous takes down government & record label sites," a member of Anonymous said via Twitter.

Anonymous allegedly lobbed a denial-of-service attack that has temporarily taken down the websites for the Department of Justice, Universal Music, the Recording Industry of America and the Motion Picture Assn. of America.

The U.S. government and the F.B.I accused the "Mega Conspiracy" group of engaging in a scheme that took more than $500 million away from copyright holders and generated over $175 million in proceeds from subscriptions and advertising, according to an indictment unsealed on Thursday. The companies charged were Megaupload Ltd and Vestor Ltd.

The maximum penalties are 20 years for conspiracy to commit racketeering and to commit money laundering and five years for each count of copyright infringement and five years for conspiracy to commit copyright infringement.

However, soon after U.S. federals shut down Megaupload.com, an offshoot of the website seems to have relaunched at a new address.

MegaUpload was just one of the many services that allow for the easy sharing of large files online. Others include sites such as Mediafire and Rapidshare and cloud storage services that allow for shared folders such as Box.net and Dropbox.