WASHINGTON (CBSDC) – Anonymous is claiming a major victory in its war against the Islamic State of Iraq and Syria militants, reports the International Business Times.

The computer hacking group says it took down an ISIS propaganda site on the “dark web” and replaced its with an advertisement for Prozac.

The dark web is a section of the Internet that requires specialist software tools to access, such as the Tor browser. It was originally designed to protect privacy, but it is also associated with illegal activities.

It is often confused with the deep web, which is a vast section of the surface internet not indexed by search engines such as Google. The deep web is believed to be about 95 percent of the internet.

A post on the Tor anonymity network read: “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 ad is for a site that describes itself as “the number one bitcoin online pharmacy,” which sells medication ranging from Viagra to Prozac.

The ad and the message were put up less than a week after the original site was created.

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