"The [voice] recorder will be sent for additional analysis to Germany on February 22," the source told RIA Novosti.
On October 31, a Russian-operated airliner, carrying 224 people, crashed in the Sinai Peninsula en route from Sharm el-Sheikh to St. Petersburg. All people on board died in what has become the biggest disaster in Russian civil aviation history.
According to the Russian security officials, the crash occurred due to a terrorist attack. Daesh jihadist group, which is banned in Russia and many other countries, claimed responsibility for the tragedy.