The ultra-conservative Salafist movement, which is said to be the fastest growing branch of Islam, has been blamed for being behind many of the recent violent protests over an anti-Muslim film which appeared on the internet. Jenny Cuffe investigates the spread of Salafism across the countries of the Arab Spring. She asks what threat it poses to democracy in the whole region and also examines concerns in Europe that Salafists now represent a significant security risk. Presenter: Jenny Cuffe Producer: Ian Muir-Cochrane.