ISIS militants have taken control of cities in Iraq and Syria . The group includes jihadists who have traveled from Europe and elsewhere to fight . Citizens from France , Germany , Denmark , U.S. have carried out bombings in Iraq and Syria . They see themselves as the foot soldiers of a fledgling Islamic emirate at the heart of the Arab world . Security forces are concerned that Western militants may return home to cause chaos .
ISIS militants have taken control of cities in Iraq and Syria . The group includes jihadists who have traveled from Europe and elsewhere to fight . Citizens from France , Germany , Denmark , U.S. have carried out bombings in Iraq and Syria . Security forces are concerned that Western militants may return home to cause chaos .