Lucky -- this could have been a very bad day for the Russians
A few days ago ISIS claimed it has destroyed another helicopter of the Russian air force in Syria. Now they've also released the video that confirms it.
What you can see on the video is two helicopters on the ground along with two armored cars. The helicopters are a Mi-35 gunship whose engines are off and a Mi-8 transport whose rotor blades are moving from the beginning of the video.

Almost simulatenously the Mi-8 transport lifts off and the idle Mi-35 explodes, probably hit by a guided anti-tank missile. The two Russian armored cars on the scene (a GAZ Tigr and a BPM-97) also scramble to safety after that.
See for yourself:
BIG! First #video of the #ISIS attack on the #Russia|n army helicopter near Palmyra. The attack was made using a direct ATGM hit.. #Syria pic.twitter.com/nopw211NOy
— Rami (@RamiAILoIah)November 3, 2016
Better resolution: link
We don't know for sure what happened before the video starts since the Russians have not commented on the loss, however it seems almost certain that Mi-35 was destroyed by the enemy since the surviving transport helicopter can be seen deploying flares to protect itself.
Also it seems most likely that we're looking at an evacuation scene, with the transport helicopter there to evacuate the crew of the gunship which has been forced down for some reason (either enemy action or malfunction).
It doesn't look like Russians suffered casualties in the attack. ISIS missile strikes the idling empty helicopter at a moment when the evacuation helicopter is already lifting off implying the Mi-35 crew is already on board. -- In other words ISIS struck the "wrong" (or the "right" depending on your perspective) helicopter.
A Mi-8 is normally crewed by four, and Mi-35 by two men.
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