"A total of 1,547 pieces of Tu-154 wreckage has been found and raised to the surface, including 311 founded in the past 24 hours," the source said.
The Russian Defense Ministry's Tu-154 aircraft en route to Syria from Moscow crashed soon after takeoff near Russia's Black Sea resort of Sochi early on Sunday.
The plane was carrying 92 people including eight crew members, 64 musicians of the Alexandrov Ensemble, nine reporters, head of Spravedlivaya Pomoshch (Fair Aid) charity Elizaveta Glinka, and two federal civil servants.
Fifteen bodies have been recovered so far.
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