On 20 April 1978, Soviet air defense shot down Korean Air Lines Flight 902(KAL 902) near Murmansk, Soviet Union, after the civilian aircraft violated Soviet airspace and failed to respond to Soviet ground control and interceptors.

Soviet Air Defence Forces initially identified it as part of the US air reconnaissance force, which carried out thousands of flights along Soviet borders annually at the time. Captain Alexander Bosov, pilot of the Sukhoi Su-15 that brought down Flight 902, saw Asian logogram characters on the tail of the Korean aircraft, and reported this to the ground control. Despite this, Vladimir Tsarkov, commander of the 21st Soviet Air Defence Corps, ordered Bosov to take down the plane, as the plane failed to respond to repeated orders to land, and was approaching the Soviet border with Finland.

The Su-15 opened fire, forcing the plane to descend, and killing two of the 109 passengers and crew members aboard Flight 902. The plane made an emergency landing on the frozen Korpiyarvi lake (not to be confused with the Korpijärvi lake) near the Finnish border.