The S-300 is a later Russian long range surface-to-air missile systems. The S-300 system was developed to defend against aircraft and cruise missiles for the Soviet Air Defense Forces. Subsequent variations were developed to intercept ballistic missiles.
During the military exercise one of the S-300 rockets was deployed, but something went wrong. The rocket plummeted back down to the ground right on top of the S-300. With spectators nearby, it's a miracle that no one was seriously injured.