The FBI has carried out over 40 searches in an investigation into cyberattacks launched by the Anonymous group in support of whistle-blower site Wikileaks.
The swoop on Thursday was part of an international police operation that included the Metropolitan Police Central eCrime Unit (PCeU), the FBI said. It follows the arrest of five young men in the UK on suspicion of involvement in the same Operation Payback series of distributed denial-of-service attacks (DDoS).
Anonymous's Operation Payback took down sites like visa.com after the company stopped accepting Wikileaks' payments. Credit: Elinor Mills/CNET News
"FBI agents today executed more than 40 search warrants throughout the United States as part of an ongoing investigation into recent coordinated cyberattacks against major companies and organisations," the FBI said in a statement on Thursday. "The victims included major US companies across several industries."
The Anonymous group of online activists has claimed responsibility for a series of successful attacks against websites belonging to businesses including Visa, MasterCard and PayPal, which stopped processing payments destined for Wikileaks.
The five men arrested in the UK have been granted police bail, the Met said in a statement on Friday. The three youngest — who are aged 15, 16 and 19 years old — must report to police on 13 April, while the oldest two — aged 20 and 26 — must report on 14 April.
The international police operation into the Operation Payback attacks was led by the PCeU, a Met spokeswoman told ZDNet UK. The other participants were: the FBI; the US Secret Service; and the national criminal police departments of the Netherlands — Korps landelijke politiediensten (KLPD), Sweden's Rikskriminalpolisen (RKP) and Germany's Bundeskriminalamt (BKA).
French authorities were also involved, according to the FBI.
Antivirus companies have put out updates to detect the Low Orbit Ion Canon tool thought to have been used in the attacks, the FBI said, adding that the US's National Cyber-Forensics and Training Alliance is helping in the investigation.
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