On September 1, 1983, the South Korean airliner servicing the flight was shot down by a Soviet Su-15 interceptor. The Boeing 747 airliner was en route from Anchorage to Seoul, but due to a navigational mistake made by the KAL crew the airliner deviated from its original planned route and flew through Soviet prohibited airspace about the time of a U.S. aerial reconnaissance mission. The Soviet Air Forces treated the unidentified aircraft as an intruding U.S. spy plane and destroyed it with air-to-air missiles, after firing warning shots which were likely not seen by the KAL pilots.
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