London's Metropolitan Police Central e-Crime Unit announced on its website Tuesday that it had arrested a 19-year-old man at a residence in Essex the previous evening.

"The arrest last night has led to the examination of a significant amount of material," the statement said. "These forensic examinations remain ongoing. The PCeU was assisted by officers from Essex Police and have been working in cooperation with the FBI."

London police authorities, also commonly known as Scotland Yard, did not explicitly say that the arrested teenager was connected with LulzSec, the shadowy online group that has been exposing security flaws and perpetrating "hacktivism" across a number of websites, including the US Senate, the American public broadcaster PBS and even the CIA.

However, a spokesperson for Scotland Yard, told the BBC that "the arrest follows an investigation into network intrusions and distributed denial of service attacks against a number of international business and intelligence agencies by what is believed to be the same hacking group."

LulzSec may have UK census data

A group purporting to be LulzSec announced on Monday that it had obtained British census data and that it would release it soon.

"We have blissfully obtained records of every single citizen who gave their records to the security-illiterate UK government for the 2011 census," the group apparently wrote.

However, as of Tuesday afternoon, LulzSec posted to its Twitter account: "I'm not seeing 'we hacked the UK census' on our twitter feed or website... why does the media believe we hacked the UK census?"

"Just saw the pastebin of the UK census hack," the group posted just a few minutes later. "That wasn't us - don't believe fake LulzSec releases unless we put out a tweet first."

Meanwhile, the Office of National Statistics in London told The Telegraph newspaper that while it was aware of the LulzSec claim, it was looking into the matter to discover if it was true.

"We are working with our security advisers and contractors to establish whether there is any substance to this," it said.

"The 2011 Census places the highest priority on maintaining the security of personal data. At this stage we have no evidence to suggest that any such compromise has occurred."

Author: Cyrus Farivar
Editor: Stuart Tiffen