NTSB just seems redundant at this point. I've always seen NTSB as coming in to figure out why an aircraft has crashed when the cause is unknown. We know it was shot down, the question is by what and by whom.

I figure CIA would be better informed on weapon systems from other nations than the FBI would. I'm sure they've got their specialists but I can't imagine them being as trained on self propelled SAM systems as much as the CIA might. Maybe MANPAD systems but theater air defense systems seems like a stretch. I could be mistaken though...