Access to the British Home Office website's was disrupted Saturday after the hacking group Anonymous called on supporters to hit the site with denial-of-service attacks, the BBC reported.

The BBC said the site became inaccessible at about 21:00 BST (4 p.m. EDT) Saturday; it said a low-graphics version was available at times later. By early Sunday BST, the site was back to normal.

In a series of Twitter updates, Anonymous claimed that its attacks affected the websites of Britain's Ministry of Justice and Prime Minister David Cameron's office as well. A spokesman for the prime minister denied that, but the BBC reported that access to the site was slow for a while. ZDNet said all three British government sites were down at one time.

Anonymous is an amorphous worldwide network of computer hackers who use denial-of-service attacks and other types of network disruption to call attention to a series of political causes. SecurityNewsDaily reported Tuesday that Anonymous' United Kingdom faction had called for a DOS attack on the Home Office site to protest the extradition of three British citizens to the United States. The Home Office is responsible for domestic security in Britain.

The hacking group announced April 1 on its AnonOpUK Twitter feed that it was launching "Operation Trial At Home."

The three citizens are Gary McKinnon, Christopher Harold Tappin and Richard O'Dwyer, SecurityNewsDaily said:

McKinnon, a Scottish systems administrator, was arrested in 2002 for allegedly hacking into U.S. military and NASA computers in 2001 and 2002 and deleting files and copying data. Tappin, a retired British businessman, is accused by the U.S. government of exporting materials to Iran that can be used to build surface-to-air missiles. The owner of TVShack.net, O'Dwyer has been charged with hosting copyrighted materials on his site; the U.S. Justice Department has been seeking his extradition since last May.

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