It's clearly a MiG-29 "Fulcrum" firing an air-to-air missile at the drone as it flew along the Abkhazian Black Sea coast. However, neither Georgia nor (theoretically) the Abkhazian rebels have MiG-29s -- in fact, the only ones even close to the area with the type are the Russians, who have been supporting the Abkhazians (and the South Ossetians) in their attempt to break away from Tbilisi.
According to radar tracks, the MiG took off from an airfield in Abkhazia, flew over the Black Sea, shot down the drone, and then flew to Russia.
The Abkhazians claim it was one of their own L-39s that shot down the drone, but given the plane in the video is clearly a twin-tailed aircraft (as opposed to a single tail L-39), this claim is laughable.
But why would the Russians risk being filmed blatantly violating Georgian airspace. Two theories spring to mind:
- The drone was not in Georgian airspace -- but nobody's denied the drone's position.
- There was something else that the drone could not be allowed to film.