Russian pilots teamed up with Serbian air crews to fly combat jets and helicopters during annual BARS-2017 military drills that kicked off in Russia. The rigorous war games involved up to 20 aircraft.

Fighter jet and helicopter pilots have been hitting aerial and ground targets at an airbase lying some 500km away from Moscow. BARS 2017 exercise also involved dogfight drills and interception of mock enemy aircraft, Russia’s Defense Ministry said.

A Ruptly video showed MiG-29UB fighter jets traversing the skies over an airfield in Lipetsk Region as paratroopers performed fast-rope landings from Mi-8 helicopters.

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During the drills, which are set to wrap up by the end of this week, mixed Mig-29 crews performed aerial stunts and fended off mock enemy attacks.

The flight maneuvers continued into the night when pilots mastered their landing skills in unfamiliar terrain.

The first BARS war games were staged in 2015 near Astrakhan in southern Russia, and the event has been staged annually since then.