The FBI has issued warrants for the arrest of 40 people suspected to have been involved in the Operation Payback distributed denial-of-service attacks run by the Anonymous group.
The announcement followed the news that UK police had arrested five suspects in connection with the attack, which brought down the web sites of payment companies that had blocked WikiLeaks donations, including MasterCard and PayPal.
The FBI said that it is taking part in a global campaign to track down Anonymous members using the Low Orbit Ion Canon tool that the group distributes.
"The FBI is working closely with its international law enforcement partners and others to mitigate these threats," the agency said in a statement.
"Authorities in The Netherlands, Germany and France have also taken their own investigative and enforcement actions. Major internet security software providers have instituted updates so they will detect the so-called Low Orbit Ion Canon tools used in these attacks."
V3.co.uk has received a press release (PDF) from a source claiming to be from the Anonymous group, threatening the UK government with retribution if the five people arrested today are prosecuted.
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