S-300 air defense missile system fires during exercises of the Air Defense Forces, as part of Vostok-2018 (East-2018) drills at the Telemba training ground, Republic of Buryatia, Russia, September 12, 2018. Vostok-2018 (East-2018) drills are the biggest since a Soviet military exercise, Zapad-81 (West-81) which took place in 1981.