Most evidence point in a single direction: The separatists got the BUK somehow from Russia (Stolen&#x2F;Supplied&#x2F;Holiday...), and that the downing of the aircraft was a mistake (As you say neither part in this conflict has any interest in downing a civilian jet).<p>What we should remember here is that &quot;who did it&quot; in this matter is more a matter of who was in command and who provided the hardware, rather than who pushed the button.<p>This is the most likely hypothesis but there are others. Apart from the craft being downed by Ukraine (Nothing in the report points in that direction), another hypothesis one would be actual Russian personnel, rather than Ukrainian separatists, operating from inside Donetsk. That would be hugely controversial, but hard to prove.