A massive search operation is underway in the Black Sea in an effort to recover the plane's black box
A national day of mourning has been declared in Russia after a Syria-bound military plane crashed into the Black Sea reportedly killing all 92 people on board.
A massive search operation is underway in an effort to recover the jet’s black box and the passenger’s bodies.
Some fragments of the plane have been found but initial reports that the fuselage was sighted have been denied.
The plane, a Russian Defence Ministry TU-154, was carrying dozens of Red Army Choir singers, dancers and orchestra members to Syria where they were meant to entertain Russian troops in the run-up to the New Year.
Russian Transport Minister Maxim Sokolov told reporters on Monday that pilot error or a technical fault were the most likely explanations for the tragedy.
"The main versions (for the crash) do not include the idea of a terrorist act," Sokolov told a news conference in Sochi, the RIA news agency reported.
"So we are working on the assumption that the reasons for the catastrophe could have been technical or a pilot error."
The plane reportedly went down in the Black Sea shortly after taking off from the southern city of Adler where it had been refuelling.
It disappeared from radar just two minutes after it took off at 5:25 am (02:25 Irish time) on Christmas Day.
Flags were flown at half-mast around Russia on Monday as mourners placed flowers at the airport in Sochi, southern Russia, where the plane took off from, and in front of the Moscow headquarters of the Russian Army's Alexandrov song and dance troupe.
Nine Russian reporters were also on board as well as military servicemen.
Elizaveta Glinka, a doctor, charity worker and prominent member of President Vladimir Putin's advisory human rights council was also on board.
In Monday, Russian Defence Ministry spokesman Major-General Igor Konashenkov said 11 bodies had been recovered so far and that a huge sea and air search operation involving around 3,500 people was being expanded.
Thirty nine ships, five helicopters, a drone, and more than 100 divers were involved in the search and soldiers were scouring the Black Sea coastline as well.