London’s Metropolitan Police arrested a 19-year-old Essex man Tuesday in an investigation that may be linked to the tweet-happy hax0ring gang LulzSec.

“The arrest follows an investigation into network intrusions and Distributed Denial of Service (DDoS) attacks against a number of international business and intelligence agencies by what is believed to be the same hacking group,” the police announced in a statement.

“The teenager was arrested on suspicion of Computer Misuse Act, and Fraud Act offences and was taken to a central London police station, where he currently remains in custody for questioning.”

The Guardianidentified the suspect as Ryan Cleary of Wickford, Essex. In May, the griefer group Anonymous — now a LulzSec ally — outed Cleary as a Anonymous member called “viraL” who’d attempted an internal coup in an Anonymous chat room. Phone calls to Cleary’s last known number went directly to voice mail Tuesday.

LulzSec, though, denies that it’s lost a man. “Ryan Cleary is not part of LulzSec; we house one of our many legitimate chatrooms on his IRC server, but that’s it,” the group tweeted in response to the news. “Clearly the U.K. police are so desperate to catch us that they’ve gone and arrested someone who is, at best, mildly associated with us. Lame.”

LulzSec won overnight attention when it cracked PBS last month to protest Frontline’s hour-long documentary on WikiLeaks. In that hack, the group stole and posted thousands of stolen passwords, and put up a fake news story on a PBS Newshour blog.

The group has also claimed responsibility for hacking multiple Sony websites, and Fox.com, where the group stole and posted 363 employee passwords and the names, phone numbers and e-mail addresses of 73,000 people who had signed up for audition information for the upcoming Fox talent show The X-Factor. More recent hacks have included defacement of two regional websites for InfraGard — a kind of cybersecurity neighborhood watch sponsored by the FBI — and crude DDoS attacks against the CIA and other lulzkillers.

While its hacks have been largely opportunistic, LulzSec is distinct for its ability to work a crowd, using Twitter to taunt its enemies and engage its fans. As of writing, it has over 230,000 Twitter followers, and LulzSec-inspired graffiti has begun to appear. The group’s fame has come at a price, of course, and an anonymous group of “web ninjas” has set up a blog dedicated to publicly identifying LulzSec members by correlating nicknames from IRC chat logs.

Updated 15:00 EDT with LulzSec response.