No news yet on cause and aircraft not yet found.

However, lack of mayday call from pilot suggests it could be explosion.

http://www.bbc.com/news/world-europe-38430164


Quote:

Russian military plane disappears from radar near Sochi Russia's Tu-154 military transport planes have been regularly flying to Syria, escorted by Russian bombers (file picture) A Russian military plane has disappeared from radar just minutes after take-off from the Black Sea resort of Sochi. The defence ministry said its Tu-154 aircraft had 91 people onboard, including service personnel, a military music band and reporters. The plane disappeared from radar 20 minutes after taking off from Sochi's Adler airport at 05:20 (02:20 GMT). Unconfirmed reports said it was flying to Syria's Latakia province. Russian Defence Ministry spokesperson Igor Konashenkov said soldiers, members of the famed Alexandrov military band and nine reporters were on board the plane. He said they were flying to Syria to take part in a new year's performance for Russian troops deployed in Syria. A huge search operation was now under way, Mr Konashenkov added. Russia - a key ally of Syrian President Bashar al-Assad - has been carrying out air strikes against what it described as terrorist groups. The aircraft went missing as it was manoeuvring over Russia's territorial waters, a source at the emergency ministry was quoted as saying by Russian news agencies.

Wow.  This guy calls himself a lefty human rights activists

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