Two American servicemen have been shot dead in a bus at Frankfurt airport in Germany. Two other US servicemen were wounded. The servicemen were being moved from their base in Britain to a big military complex outside Frankfurt. The 21-year old gunman who tried to run away after the shooting, was captured. He was born and raised in Germany after his parents moved there from Kosovo about 40 years ago. His uncle in Kosovo said he was a devout Muslim who worked in the airport. Motivation of the attack is not yet known.