The hacktivist collective, Anonymous, has reportedly taken down an ISIS propaganda website as part of its online struggle against the terrorist group.
The site, which has been available on the dark web for around a week, was replaced by an ad for Prozac, IB Times reports.
After the attack, visitors to the site saw the message, “Too much ISIS. Enhance your calm. Too many people are into this ISIS-stuff. Please gaze upon this lovely ad so we can upgrade our infrastructure to give you ISIS content you all so desperately crave.”
The dark web is only accessible through the TOR internet browser, and does not show up on search engines.
Initial reports that the operation was carried out by Ghost Security Group turned out to be inaccurate, according to IB Times.
Ghost Security Group say they focus on intelligence gathering work, and pass on information they find to the FBI.
Anonymous announced its intention to target ISIS online in the wake of the Nov. 13 terrorist attacks in Paris.
“Anonymous from all over the world will hunt you down,” an Anonymous spokesman said in a video, Daily Mail reported.
“You should know that we will find you and we will not let you go. We will launch the biggest operation ever against you. Expect massive cyber attacks. War is declared. Get prepared,” he added.
Opinion is divided on the effectiveness of such attacks. Britain’s security minister, John Hayes, said he was “grateful for any of those who are engaged in the battle against this kind of wickedness,” according to IB Times.
But others are not convinced.
“Anonymous does not coordinate their calls for social media account closures with government officials,” said Michael Smith, a counter-terrorism adviser to the U.S. Congress. “This can actually serve as a form of interference, which ultimately benefits the enemy. From my own personal experience, I can assure you this has been the case, especially following the attacks in Paris.”