Kiev, Ukraine (CNN) -- Did a Russian fire the missile that downed Malaysia Airlines Flight 17? That depends on who you ask. A top Ukrainian official says he has no doubt. Vitaly Nayda, Ukraine's director of informational security, told CNN the person who shot down the flight was "absolutely" a Russian. "A Russian-trained, well-equipped, well-educated officer ... pushed that button deliberately," he said. "We taped conversations" between a Russian officer and his office in Moscow, Nayda said. "We know for sure that several minutes before the missile was launched, there was a report" to a Russian officer that the plane was coming, he said.
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The officials have determined that Russia bears some responsibility for the incident because of its support for the rebels, but they haven't been able to determine exactly who fired the missile, whether Russian military were at the site or whether the @placeholder were directly responsible for launching the missile.