FBI(LONDON) -- The FBI has joined the search for a 17-year-old Ohio girl who vanished after arriving at Atlanta's Hartsfield-Jackson International Airport on Tuesday, authorities said. The FBI Atlanta office described the missing girl, Emma Linek, as being "endangered" and in need of medication that she did not have at the time of her disappearance. "Another thing that is of concern is that Emma has no known connection to the city of Atlanta or has never been here before or does not know anybody in Atlanta that we know of," Christopher Macrae, the special agent in char...