LONDON, ENGLAND - NOVEMBER 16:  Flowers and messages are left in Trafalgar Square as Londoners gather to observe a minute's silence for the victims of the terrorist attacks in Paris on November 16, 2015 in London, England. The minutes silence, held at 11:00 GMT, was observed across Europe to pay respects to the victims of a series of terror attacks across the French capital on Friday, which left at least 129 people dead and hundreds more injured.  (Photo by Ben Pruchnie/Getty Images)