AKIPRESS.COM - A huge search operation is continuing "round the clock" in Russia, after a Russian military plane with 92 people on board crashed into the Black Sea.

More than 3,000 people, including 109 divers, as well as ships, planes, helicopters and submersibles are involved in the operation near Sochi, BBC reported.

The Tu-154 plane - carrying soldiers, members of a famed army music ensemble and reporters - was heading for Syria.

All those on board the aircraft are feared dead after Sunday's crash.

Monday has been declared a day of national mourning across Russia.

"As darkness fell, the operation in the crash area is continuing non-stop," defence ministry spokesman Maj Gen Igor Konashenkov said at a briefing late on Sunday.

He said that powerful spotlights were being used overnight as the search teams were looking for plane debris.

Officials earlier said they were were focusing on the area of 10.5 sq km (four square miles) just off the coast.

The defence ministry said in a statement: "Fragments of the Tu-154 plane of the Russian defence ministry were found 1.5km (one mile) from the Black Sea coast of the city of Sochi at a depth of 50m to 70m (165-230ft)."

Earlier on Saturday, 11 bodies had been recovered.