Volunteers were encouraged by members of the loosely bound Anonymous collective to download a tool to pepper the websites of financial firms who had turned their back on WikiLeaks - including MasterCard, Visa and Swiss bank PostFinance as well as PayPal - with junk traffic.
FBI investigators are proceeding on the assumption that some used botnets of compromised machines in order to launch a more potent distributed denial of service attack against PayPal, knocking its corporate blog offline for at least several hours.
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