It's an international air disaster in a war zone -- a commercial flight with almost 300 people on board shot down in eastern Ukraine. As new details emerge, here is a look at basic questions about the tragedy: Was the plane shot down? All evidence so far says yes. President Barack Obama declared Friday that a surface-to-air missile blasted the Malaysia Airlines Boeing 777 on Thursday over the Donetsk region of Ukraine near the Russian border. According to a senior American official, a U.S. radar system saw a surface-to-air missile system turn on and track an aircraft right before plane went down.
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Donetsk rebel official: Plane shot down, but not by us
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Malaysian official says the crash site's integrity has been compromised
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President Obama says evidence points to a missile strike by pro-Russian rebels
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Russia could face increasing international isolation and tougher sanctions
If the rebels fired a @placeholder missile, as suspected, the international backlash could be severe.