Secretary of the Ukrainian National Security and Defence Council Yevgeny Marchuk has confirmed that today there is only one version of the T-154 liner crash - it was hit by a S-200 missile fired from an antiaircraft system during exercises of the Ukrainian air-defence forces. Yevgeny Marchuk said this on Thursday at Kirovskoye airport when meeting Russian Security Council Secretary Vladimir Rushailo. The Russian delegation, headed by Vladimir Rushailo, arrived in the Crimea on Thursday to complete, jointly with the Ukrainian side, the investigation of the T-154 crash which occurred on October 4th. According to Vladimir Rushailo, the state commission for investigating the air crash, headed by him, has already drawn its conclusions, and the Ukrainian side has agreed with them. For his part, Yevgeny Marchuk said that "now it is necessary to find out how it happened." It is with this aim in view, he underscored, that the Russian State Commission with Vladimir Rushailo at the head, has arrived at the invitation of the Ukrainian side. Yevgeny Marchuk said that on Thursday the commissions of the two countries would make investigatory actions at the test ground from which the missile was fired.