The stories in which the Donetsk People's Republic -- the initial claim that they had the missiles didn't come from Kiev, though the claim that they had used them to shoot down this plane did -- claimed to have captured the Buk missiles [0] were before this incident (and they've apparently shot down Ukrainian military aircraft recently beyond any altitude that MANPAD missiles would reach), so the furious backpedal and claiming they don't have the technology now is somewhat dubious.

It could, though, be an honest retreat from a propaganda misrepresentation that has since become more of a burden than a benefit.

(Incidentally, I upvoted the parent because even though the claim may be dubious, noting the fact that the claim has been made is a valuable addition to the conversation, IMO.)

[0] referenced in my earlier post: https://news.ycombinator.com/item?id=8048607