Hackathons take on IS in battle for young minds

In a small room close to the Sydney Opera House, 60 people representing a vast range of communities and industries are working feverishly to come up with ways to combat the Islamic State group's online propaganda machine.

The extremists' ideology and use of social media has struck a chord with thousands of young people across the world, drawing them to fight in Iraq and Syria or show support from their home countries.

The United States and its allies have struggled to counter the digitally savvy group, but a pair of Silicon Valley entrepreneurs are leading a grassroots charge to take on the Islamic State group in cyberspace, traveling around the world to host "hackathon" challenges.