Russian air experts have begun examining one of the flight recorders from a plane that crashed into the Black Sea on Sunday, killing 92 people.
The flight data recorder was found underwater about a mile from the shore, and the authorities say it is in “satisfactory condition”.
At least 12 bodies have been also been recovered so far, along with numerous fragments of the plane.
No cause has been established but terrorism is considered unlikely.
On board the Tu-154 jet when it crashed were 64 members of the famed Alexandrov military music ensemble, as well as one of Russia’s best-known humanitarian figures, Yelizaveta Glinka.
It was heading to Russia’s air force base in Syria where the ensemble were due to perform at a New Year’s concert.
The plane crashed soon after take-off from an airport near the city of Sochi, where it had landed for refuelling.
It disappeared from radar two minutes after taking off from Adler airport at 05:25 (02:25 GMT) on Sunday.
Media caption"Pain in my soul": The BBC’s Steve Rosenberg reports as Russia mourns its victims
Investigators hope the flight recorder could provide vital clues into why the military plane came down.
It is believed that the location of a second black box has also been established and it could be recovered shortly.
Russian officials say they an act of terror is not being considered as a possible cause. Instead they are looking into whether human error, a technical fault or a combination of factors were responsible.
