Members of the Board of Deputies of British Jews hold up signs reading "I am Jewish" and "I am Ahmed", referring to Ahmed Merabet, the Muslim policeman shot trying to defend the Charlie Hebdo cartoonists, during an event in London, January 18, 2015. 17 people were killed in three days of violence that began when two Islamist gunmen burst into Charlie Hebdo's Paris offices, opening fire in revenge for the paper's publication of satirical images of Mohammad in the past. REUTERS/Stefan Wermuth (BRITAIN - Tags: POLITICS)