Anonymous in Megaupload closure retaliation

Anonymous has taken down a number of major websites in what it is describing as its biggest such operation to date.

A Twitter account apparently affiliated to the activist collective claims that over 5,000 people are involved in a distributed denial-of-service attack (DDOS) operation to take several websites offline as "retaliation" against the closure of file-sharing site Megaupload earlier on Thursday (January 19).

The list of sites taken down includes those of the US Department of Justice, the Motion Picture Association of America (MPAA), the Recording Industry Association of America (RIAA), and the sites of major record labels Universal Music and Warner Music Group (WMG).

The FBI website was briefly taken down at around 00.45 GMT (19.45 EST), but was quickly restored. The Department of Justice, MPAA and WMG's websites were all back online as of 8am GMT (3am EST).

"Today, Anonymous has done well," a post on the Twitter account @anondaily read.

It has been alleged that Megaupload has cost copyright holders a loss of over $500 million (£320m). However, a statement issued shortly before the site's closure read: "The fact is that the vast majority of Mega's internet traffic is legitimate, and we are here to stay.

"If the content industry would like to take advantage of our popularity, we are happy to enter into a dialogue."

The Department of Justice has confirmed that four people - including Kim Schmitz., who is now known as Kim Dotcom - have been arrested in New Zealand.

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