It was suspected by Ukraine that the aircraft was shot down by a ground-to-air missile, fired by Pro-Russian separatists. Ukrainian President Petro Poroshenko called it an "act of terrorism." The cause of the crash has not yet been determined by the official investigation, which is being carried out by the . Fighting delayed investigation, but in October 2018 Dutch investigators said the plane was destroyed as a result of the explosion of a BUK missile.