NYT article on the extent of the IS's presence in Europe:
How a Secretive Branch of ISIS Built a Global Network of Killers
Believing he was answering a holy call, Harry Sarfo left his home in the working-class city of Bremen last year and drove for four straight days to reach the territory controlled by the Islamic State in Syria.
He barely had time to settle in before members of the Islamic State’s secret service, wearing masks over their faces, came to inform him and his German friend that they no longer wanted Europeans to come to Syria. Where they were really needed was back home, to help carry out the group’s plan of waging terrorism across the globe.
