Recovery teams have retrieved one of the flight recorders from the Tupolev Tu-154B which crashed in the Black Sea on 25 December.
The device was located in the early morning by a remote-controlled vessel some 1.6km from shore, at a depth of 17m, says the Russian defence ministry.
It will be transferred to a military research station in the Moscow suburb of Lyubertsy for analysis, the ministry adds. It has yet to clarify whether the device is the flight-data or cockpit-voice recorder.
Search teams have started recovering large sections of the Tu-154.
The defence ministry says that a side panel of the fuselage, with windows, measuring 3.5m by 4.5m, is among the parts found.
It adds that fragments from the aft-mounted Kuznetsov NK-8 engines have also been located on the sea floor.
Manned submersibles have been added to the resources being used to hunt for parts of the jet, off the coast of Sochi, while a heavy-lift cargo crane has also been brought into the area.
The ministry says 45 ships are involved in the search effort.
“All the parts found have been delivered ashore and transferred to the investigating authorities,” it adds.
The emergency situations ministry says the search has continued despite deteriorating weather conditions.
Surface vessels are searching over 100km² of the Black Sea to locate debris from the aircraft. Twelve casualties have been recovered from the 92 occupants of the aircraft.
Source: Cirium Dashboard