A US refueling aircraft crashed in western Iraq while a second plane involved in the incident landed safely, US military informed on Friday.It further clarified that the crash was not a result of any hostile or friendly fire.“One of the aircraft went down in western Iraq, and the second landed safely. This was not due to hostile fire or friendly fire,” US Central Command, which is responsible for American forces in the Middle East, said in a statement.The KC-135 tanker marks at least the fourth US military aircraft lost in the Middle East conflict, after three F-15E fighter jets were earlier shot down in a friendly-fire incident over Kuwait.