The threat of far-right extremism is on the rise, warned security minister Ben Wallace earlier this week. But what can be done to curb it? EU counter-terrorism coordinator Gilles de Kerchove says "we should deprive them from any sort of publicity." We also speak to an imam in Christchurch and an author who says we should challenge extremist ideology head on. (Image: Al Noor Mosque, Christchurch, New Zealand, credit: Getty Images)