(AP) -- Hackers claiming allegiance to the amorphous Anonymous movement say they've defaced several sites belonging to online defense firm Panda Security.
Anonymous supporters have been rattled by a trans-Atlantic investigation that has exposed one of the group's best-known hackers, Sabu, as an alleged FBI informant.
U.S. and British officials charged six men and one adolescent with a host of computer crimes linked to Sabu's activities Tuesday, sowing anger and confusion among supporters of the loose-knit network.
But the group fired back with an attack against dozens of Panda Security subsites, accusing the company of working with law enforcement.
The Bilbao, Spain-based Panda Security said Wednesday its main site wasn't compromised.
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More information: Panda Security: http://www.pandasecurity.com/