Russian investigators have passed over to their Ukrainian colleagues the files summing up the investigation into the cause of the TU-154 crash into the Black Sea. On October 3, the aircraft bound from Tel Aviv to Novosibirsk exploded and fell into the sea. The investigation showed that it had been downed by a war rocket of the Ukrainian air defense force conducting military exercises in the area. The submitted documents will help Ukrainian investigators identify those responsible for the tragedy, Russia's state civil aviation service told RIA Novosti. Fragments of the aircraft's cover and other clues have been submitted to Russia's research institutes and will be analyzed with the help of supersensitive equipment. According to the service's official, such an analysis is necessary to dash all the doubts regarding Ukraine's air defense force's involvement in the crash.