The self-styled 'hacking vigilante' known as the Jester has claimed responsibility for taking down the web site of the LulzSec hacking group.
The incident is the latest skirmish in an ongoing feud between the Jester and LulzSec, and the larger Anonymous group.
The Jester claims to be ex-military, and took up against LulzSec when he shut down the WikiLeaks web site with a distributed denial-of-service (DDoS) attack, claiming it was harming US troops by releasing diplomatic cables and footage from Afghanistan.
Since then the Jester has set out to disrupt LulzSec and identify its members. He has published information on one suspect known as Sabu, but this later proved false, and he now appears to have gone after the group's web site.
"www.lulzsecurity.com - TANGOS DOWN," the Jester tweeted at around 5pm GMT.
The Jester, or th3j35t3r, has been operating since the start of last year and specialised initially in taking down Moslem web sites that he claimed were recruiting terrorists.
However, he has since widened his target list and recently attacked the web site of the Westborough Baptist Church, a religious cult that pickets the funerals of soldiers and others, before turning on Anonymous and other hacking groups.
Typically the attacks take a standard DDoS approach that knocks a web site down by overloading the server with requests. The attacks usually break off within a day, but can be used to hide more serious hacking attempts.
"Let's not forget how all this started with the Sony hack. LulzSec got in there during a DoS attack that covered deeper penetration," Sophos security expert Chet Wisniewski told V3.
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