A very limited number of people, all of them either badly informed or biased, believe MH17 was shot down by a military aircraft of the Ukraine air force. Even last week (September 2017) a Dutch professor called Kees van der Pijl stated he believed MH17 was shot down by a military plane.
There is a lot of proof this is simply impossible. Even the Russian Ministry of Defense in a September 26 2016 press conference stated there were no other aircraft in the area near MH17.
The September 2016 2016 press conference by the Russian MoD was interesing as Russia proved that it lied at the press conference at July 21, 2014
After around 2:50 into the video below everyone can hear it