The Metropolitan Police has arrested two men aged 20 and 24 on charges of being members of the Anonymous and LulzSec hacking groups, following raids in South Yorkshire and Wiltshire.
The men are believed to be connected to the alias 'Kayla'. Previously reported to be a 16 year-old girl, 'Kayla' has been named as a prominent member of LulzSec.
Scotland Yard also said that it had charged two men with conspiracy to commit an unauthorised act in relation to a computer in another case. Ashley Rhodes, 26, and Christopher Jan Weatherhead, 20, are due to appear in court on 7 September.
The arrests and charges are the latest legal actions aimed at members of Anonymous and LulzSec. Police previously arrested 18 year-old Jake Davis, who is believed to have acted under the alias 'Topiary' as a member of both groups.
Police later arrested 22 year-old Peter David Gibson on charges related to Anonymous hacktivist campaigns.
Sophos senior technology consultant Graham Cluley noted that the arrests could have a psychological impact on the groups.
"Certainly the police appear to be mopping up a lot of suspected hackers in connection with the Anonymous and LulzSec hacks," Cluley said in a blog post.
"If nothing else, that should be something for other budding hacktivists to stew over."
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