British police arrested five people Thursday as part of an investigation into cyber attacks by the online group "Anonymous", which last year assailed websites that were hostile to WikiLeaks.
In a series of dawn raids in England, three teenage boys and two adult men were arrested on suspicion of breaking the Computer Misuse Act 1990, as part of an international probe, London's Metropolitan Police Service (MPS) said.
"The five males aged 15, 16, 19, 20 and 26 are being held after a series of coordinated arrests at residential addresses," a statement said.
It added: "The arrests are in relation to recent and ongoing 'distributed denial of service' attacks (DDoS) by an online group calling themselves 'Anonymous'.
"They are part of an ongoing MPS investigation into Anonymous which began last year following criminal allegations of DDoS attacks by the group against several companies.
"This investigation is being carried out in conjunction with international law enforcement agencies in Europe and the US."
The statement made no mention of which companies had allegedly been targeted by Anonymous, a loose-knit group of computer hackers.
Last year, Anonymous members launched assaults on the Amazon, Visa and Mastercard websites in apparent retaliation for the companies' decision to stop working with whistle-blowing website WikiLeaks.
WikiLeaks is under political pressure in the United States for its publication of thousands of classified US diplomatic cables, which has enraged Washington.
In a typical DDoS attack, a large number of computers are commanded to simultaneously visit a website, overwhelming its servers, slowing service or knocking it offline completely.
Under British law, it is a criminal offence to carry out "any unauthorised act in relation to a computer", punishable by up to ten years in jail and a fine of £5,000 (5,800 euros, $8,000).
"Anonymous" attacked Tunisian government websites this month and on Wednesday warned the Egyptian government of reprisals if it blocks Internet access for protestors.
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