Hackers launch revenge attack after arrests

Hackers from a group related to Anonymous launched a revenge attack against a security firm they claimed helped police to arrest "hacktivists" yesterday, leaving a message criticising "Sabu", the former head of LulzSec who turned FBI informant, betraying his colleagues.

Hackers belonging to Anonymous splinter movement AntiSec, with which Sabu was involved, defaced the website of the Spanish company Panda Security and posted a message saying: "Yeah yeah we know Sabu snitched on us. As usually happens FBI menaced him to take his sons away. We understand, but we were your family too."

It emerged yesterday that two British men were charged with computer hacking by Scotland Yard on Tuesday, which launched separate court proceedings against alleged LulzSec hackers at the same time as the FBI swoop. But police said the decision to charge Ryan Mark Ackroyd, 25, who was named in the New York court papers, and a 17-year-old youth from south London was "completely unrelated" to actions in America.

Donncha O'Cearrbhail, a 19-year-old student of Trinity College in Dublin, whose online name is Palladium, was arrested in Dublin yesterday after being named on a charge sheet from a New York court.

The Irish county councillor's son was later released without charge. A file on the case was being prepared for the Director of Public Prosecutions yesterday. The British pair are accused of two counts of conspiracy to "do an unauthorised act with intent to impair or with recklessness impairing of an operation of a computer".