HOOGEZAND-SAPPEMEER, Netherlands—In this sleepy Dutch town last December, police burst into the bedroom of 19-year-old Martijn Gonlag as he hurriedly pulled on jeans over his boxer shorts. He was hauled away on suspicion of taking part in cyber attacks by the online group calling itself Anonymous.RTWT.
Mr. Gonlag admits taking part in several attacks on websites, but he recently had a change of heart as some hackers adopted increasingly aggressive tactics.
"People are starting to grow tired of" the hackers, he said in an interview. "People are also starting to realize that Anonymous is a loose cannon."
Now he appears to be a target himself. A chat room he hosts faces frequent hack attacks, he says.
Mr. Gonlag's role reversal provides a glimpse of the unruly hunt-or-be-hunted world underpinning a string of online attacks against major companies and government bodies—incidents that have sparked a digital manhunt by law-enforcement agencies in several countries.
What once was just righteous rabble-rousing by Anonymous in the name of Internet freedom has mutated into more menacing attacks, including by a splinter group of Anonymous called LulzSec, which is alleged to have moved beyond paralyzing websites to breaking in to steal data.
The tumult over online agitators like Anonymous comes at a time when the world's computers are under unprecedented attack. Governments suspect each other of mounting cyber espionage and attacks on power grids and other infrastructure. Criminal gangs using sophisticated viruses cull credit-card and other sensitive data to steal from bank accounts.
Now "hacktivists" who populate groups like Anonymous and LulzSec, mostly young males from their teens to early 30s, have also ignited increasing concern among computer experts over the security of corporate and government systems.
It was bound to happen. These are supposedly anarchists, but mostly they're a bunch of young leftist criminals with too much time on their hands. They'll get more menacing and deadly, their attacks more brazen and malicious, and ultimately these same people will be found allying increasingly with various terrorist groups. Some of the recent bombings, in Spain, for example, were the work of anarcho-communist cells. It's all of a piece, and no coincidence that people like this are championed on the progressive left.