SOCHI — Russian rescuers found on Monday the first parts of the Syria-bound military plane that plunged into the Black Sea, as officials dismissed terrorism as a possible cause of the crash that killed all 92 people on board.

The Tu-154 jet, whose passengers included more than 60 members of the internationally-renowned Red Army Choir, was heading to Russia’s military base in Syria when it went down off the coast of the resort city of Sochi shortly after take-off on Sunday.

Investigators have yet to confirm the cause of the crash, but officials said that an act of terror was not being considered as a possible explanation, despite the plane and its black boxes still being underwater.

A spokeswoman for the Sochi-based search and rescue branch of the emergency ministry confirmed that parts of the plane had been found underwater.

"The debris is at the depth of 27 metres one mile from shore," spokeswoman Rimma Chernova said.

The Russian military added that divers had retrieved "two elements of the plane’s control mechanism."

Later the defence ministry said part of the plane’s fuselage, measuring 3.5 metres by 4.5 metres, had been recovered and brought to shore on Monday evening.

Authorities announced that the search operation would continue overnight and into the following days.

Russia’s federal security service said it is looking into four suspected causes of the crash, which do not include terrorism.

"No signs or facts pointing to a possible act of terror have been received at this time," Russia’s Federal Security Service said in a statement carried by national news agencies.

The probe is focusing on a pilot error, a technical fault, bad fuel and a foreign object in the engine as the four main scenarios, it added.

Thousands searching

The military has cordoned off part of the Sochi shore, with soldiers standing in a chain and motor boats participating in the search regularly unloading at the pier, an AFP photographer reported.

More than 3,000 people are racing to find the remaining bodies and debris in a massive operation that includes 45 vessels, planes, helicopters and drones, along with divers and remotely-operated deepwater machines.

Transport Minister Maxim Sokolov said some of the bodies could have already been carried off by the "strong current" to Abkhazia, the separatist region of Georgia, and some of its own rescue workers have joined the search operation.

Along with the first 10 bodies, 86 body fragments were brought to the Russian capital for DNA analysis, defence ministry spokesman Igor Konashenkov said.

He said searchers have finished looking over the on-land territory around the crash site while divers are working over an area with a radius of 500 metres. — AFP