It's an international flight route. Every single airline in that area was using that route until very recently. Now they're all actively avoiding it ever since that incident. MH17 was just unlucky that some russian dumbasses decided to shoot it down thinking it was a Ukranian military plane again (they shot two of those down earlier). The Ukranians are claiming that the pro-russian militias shot it down with a Buk Missile System.

Here's the area where the other planes are currently flying.

https://twitter.com/...89816774641463298/photo/1
http://en.wikipedia.org/wiki/Buk_missile_system

A TIME reporter was interviewing a militia leader who claimed that they didn't have the ability to shoot down airplanes that high up. When asked about their Buks, he promptly hung up.

https://twitter.com/...atuses/489817136408178688