Christian refugees fleeing IS reported seeing a jihadi militant disguised as a migrant. German police tracked the man down but refused to charge him because he had not committed a crime in Germany. It is feared that militants are exploiting the refugee crisis to smuggle terrorists into countries. The Assyrian Christian refugees who made the concerning/serious claim were granted asylum after being held hostage by IS. Also this week Iraqi and US officials revealed that an IS leader they captured last month was the head of a chemical weapons unit. He is now being questioned about IS’s use of chemical weapons. He had been in Saddam Hussein's Military Industrialisation Authority where his speciality was developing biological and chemical weapons. In recent months, according to Associated Press, he was working on building a similar branch for IS. See: