"The course of a criminal investigation is under the personal control of the Investigative Committee chairman [Bastrykin]," Petrenko said in a statement.
Early on Sunday, the Russian Defense Ministry's Tu-154 plane heading from Moscow to Syria with 92 people on board, including the Alexandrov Ensemble members, and nine journalists, disappeared from radar shortly after refueling and take-off from the Russian southern city of Adler, near Sochi. Fragments of the plane were discovered 1.5 kilometers (1 mile) from the sea shore of Sochi at a depth of 50-70 meters (164-184 feet).
Technical malfunction or pilot error could be among the reasons of the accident, a source in security service told RIA Novosti.
Russia’s Investigative Committee has initiated a criminal case into the catastrophe.