An American researcher says it is highly likely that the United States is responsible for the crash of a Russian passenger plane over Egypt this week. On Saturday, the Airbus A321-200 broke up in midair and crashed in Egypt's Sinai Peninsula, killing 224 people on board. An investigation is underway to find out how the disaster happened; however, the airline has said that technical faults or human errors could not have caused the tragic crash. "New information from sources with contacts in the CIA are reporting that the US recently sold ships to Egypt in return for a drone base...