The world’s biggest search engine is joining the fight against the Islamic State on one of its most active fronts—the internet.

Blocking the message and recruitment efforts of the terror outfit known as ISIL has so far been a game of whack-a-mole, as it has skillfully used the internet and social media to reach new members. No matter how hard Twitter, Facebook and other behemoths try to axe extremist accounts and content, they keep popping back up with new user names or on other platforms such as Telegram and Whatsapp.

One of the most vexing problems is how to deter aspiring ISIL members who go online to seek information about the group. Now Google says it has figured out a new approach.

Jigsaw—the New York-based technology incubator formerly known as Google Ideas, founded in 2010—is trying to deter potential ISIL recruits who are committed to the cause enough to actually seek out ISIL’s online materials. Over the past year, the think tank created and is testing the “Redirect Method” to target aspiring ISIL jihadists, Wired reported. (Google did not immediately respond to Quartz’s request for comment.)

The company, which operates under Alphabet Inc., has identified over 1,700 ISIL-related keywords. These include travel routes, fatwas (religious orders), names of extremist leaders, and more. In the project’s pilot program, which it plans to launch in a new phase this month, every time a user searches for any one of them, the search engine displays anti-propaganda ads.

So far, counter-messaging efforts have been largely ineffective, according to the Brookings Institution, because governments and other entities aren’t able to match the volume of content put up by ISIL’s virtual caliphate. The think tank explains:

It takes a network to fight a network. Despite some steps to ramp up the volume of our counter-propaganda efforts, we still lack the volume necessary to be able to compete in this space. Volume has value. And the Islamic State—either itself or with its networks—still has the advantage in numbers, and it’s managed to create an echo chamber that gives its messages a life of their own.

The hope is that a search giant like Google could make better headway. But the opposing narrative has to be as engaging as ISIL’s, Brookings Institution wrote: A mix of “sarcasm, fact-based approaches, ideological approaches, and others,” along with the use of video, could help the counter-propaganda work more effectively.

Rather than countering queries with explicit anti-ISIL marketing, Jigsaw’s ads link out to YouTube videos (in Arabic and English) showing reformed extremists, imams denouncing ISIL’s version of Islam, and covert video clips from within showing the caliphate’s hypocrisy and deplorable living circumstances. “This came out of an observation that there’s a lot of online demand for ISIS material, but there are also a lot of credible organic voices online debunking their narratives,” Yasmin Green, Jigsaw’s head of research and development, told Wired.

A pilot project, co-hosted by partners Moonshot CVE and the Lebanese firm Quantum Communications, showed some success with the approach: More than 300,000 people found their way to the anti-ISIL YouTube channels over a period of two months. The click-through rate for Jigsaw’s campaign was triple that of a typical ad campaign at 9%. And people spent “twice as long viewing the most effective playlists than the best estimates of how long people view YouTube as a whole,” Wired reported.

Although there is no guarantee that attention and engagement will actually dissuade people from joining ISIL, targeted videos are a step up from keyword detection and content blocking that have been used so far.

“These are people making decisions based on partial, bad information,” Green told Wired. “We can affect the problem of foreign fighters joining the Islamic State by arming individuals with more and better information.” Green said the project has no intention of tracking and surveilling individuals to arrest them.

Next up on the agenda is extremism in the US. The project will target violent white supremacists—another group that has been worryingly gaining traction on Twitter in recent years.