O’Reilly knows what Jesus would do…

Mr Wilders, 51, had left the conference centre, where he made a speech criticising Islam, shortly before the incident.

“I want to send a message that if you use violence to suppress free speech the only effect is that we’ll do it even more,” Mr Wilders said, adding “we must show we’ll not be intimidated.”

The platinum-haired Mr Wilders, whose Freedom Party (PVV) gained popularity in the Netherlands on an anti-Islam ticket, denied that a cartoon exhibition would be provocative.

“I don’t want to provoke, but at the same time we must show that we’re standing for freedom of speech,” Mr Wilders said.

Ever since forming his own party in 2006, the firebrand politician has been a divisive figure in the Netherlands, which prides itself on its long but fading tradition of multi-cultural tolerance.

Mr Wilders himself has no hesitation in branding the Koran as a “fascist” book and have before likened it to Hitler’s Mein Kampf.

But the politician is facing prosecution in the Netherlands after a controversial statement last year during local government elections in which he vowed to ensure fewer Moroccans in the Netherlands.

Public prosecutors received more than 6,000 complaints of discrimination after television footage in March last year showed Mr Wilders asking party faithful in The Hague whether they wanted “fewer or more Moroccans in your city and in the Netherlands?”

“Fewer, fewer!” the crowd shouted with a smiling Mr Wilders saying: “We’re going to organise that.”

The Isil claim marks the first time that the extremist group, which has captured swathes of territory in Syria and Iraq using brutal methods, is alleged to have carried out an attack in the United States.