It seems you can't keep a top hacker down. After a month's absence, amid rumours that the law had finally caught up with him, Sabu, the leader of notorious 'hacktivist' group, Lulzsec, appears to have returned.

Lulzsec wrought havoc earlier this year by hacking major firms like Sony and America's Public Broadcasting Service. Sabu also claimed responsibility for hacking major US security firm, HB Gary, earlier in the year in the name of Anonymous.

During the rampage, Lulzsec posted hundreds of thousands of usernames and passwords online. Despite the illegalities of the acts, Lulzsec's actions were notable for the lack of unanimous condemnation from authorities. Indeed, their actions brought the importance of online and computer security to the world's attention to an astonishing degree - appearing on the front page of almost every major news website in the world. Even the security community generally avoided damning Lulzsec on account of their actions not appearing to be malicious and their success at educating the public of the dangers that overtly-criminal hackers already know about.

Nonetheless, after time was called on a 50-day rampage, the group merged back into the Anonymous hacking collective, only for it to reappear with more shenanigans shortly afterwards. However, things quickly soured with associate 'Topiary' being arrested on a Scottish island and rival hackers posting detailed documents (called 'dox') supposedly exposing who Sabu was.

He then left a final Tweet:

The greatest trick the devil ever pulled was convincing the world he did not exist. And like that... he is gone.

He was not heard from again until today when he posted the following:

ATTN: I never left, I am NOT @AnonSabu or any of those posers. I wasn't owned, arrested, hacked or any of the other rumors. Go get lives

Despite suggestions that the reawakening of the Twitter account could be due to it being hacked or being used as a 'honeypot' trap designed to flush out associates, the recent activity matches what was seen previously.

He also posted:

They tried to snitch me out, troll me, dox every one around me, bait me into endless arguments but theres one thing they can't do: STOP ME!

At the time of writing, he'd posted almost thirty times in just a few hours - matching Sabu's previous prolificacy. The language(s) used in his tweets is certainly similar and the activist/hacktivist topics of his tweets also match.

It suggests that one of the world's most-wanted cyber "criminals" is still at large despite international law enforcement's efforts to catch him: remarkable in this day and age.

Sabu's reappearance coincides with protests occurring in Wall Street which are supported by Anonymous. The protests have, thus far, generated minimal mainstream media attention although Al Jazeera has been following the story.

A live stream of events can be seen here.