Russian officials said they cannot rule out terrorism in the crash of a military plane en route to Syria which plunged into the Black Sea minutes after it took off on Sunday, killing all 92 people on board.
Earlier, a Russian official had downplayed any suggestion of terrorism. But on Sunday afternoon, after being asked if investigators are looking into a possible terror attack, Russian Transport Minister Maxim Sokolov said an "entire spectrum" of possible reasons is being considered.
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92 feared dead in Russian military jet crash
A Russian military jet crashes en route to Syria carrying dozens of the Red Army Choir on Sunday. The defence ministry says there are no survivors.
He added it was premature to speculate about what caused the tragedy in which dozens of Red Army Choir singers, dancers and orchestra members lost their lives.
There was speculation by a few aviation experts, echoed by some officials, that terrorism could not be ruled out given the suddenness with which the plane disappeared and the size of the debris field.
"For us the worst version is an act of terrorism, because if this is the case, this will mean that we have paid another bill for Aleppo," Vadim Lukashevich, an aviation expert, told Dozhd, an independent television station.
Major-General Igor Konashenkov, a Russian military spokesman, told reporters that no one survived after the ageing Soviet-era jet, which originally set out from Moscow, crashed shortly after a refuelling stop at the airport in the Black Sea resort city of Sochi.
"The area of the crash site has been established," Konashenkov said. "No survivors have been spotted."
Russian news agencies reported that the plane crashed about two minutes after taking off in good weather. It had not sent a distress signal before disappearing from the radar, and no life rafts had been found by 3000 people engaged in the recovery. Konashenkov described the captain of the jet as an experienced "first-class pilot".
![Flower tributes in front of portraits of Russian TV journalists who were killed in the crash.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/t/f/0/image.related.articleLeadwide.620x349.gthrqd.png/1482750667744.jpg)
In nationally televised comments Russian President Vladimir Putin, speaking in St Petersburg, declared December 26 a national day of mourning and said the cause of the crash would be carefully investigated.
Viktor Ozerov, head of the defence affairs committee in the upper house of Russian parliament, said in remarks carried by the state news agency RIA Novosti that he "totally excludes" terrorism as a possible cause. He cited among his reasons the fact that the aircraft took off from a heavily guarded military aerodrome in Moscow.
![Recovery operation: More than 3000 people were involved in the rescue.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/s/x/u/image.related.articleLeadwide.620x349.gthrqd.png/1482750667744.jpg)
Konashenkov said the jet, a Tupolev 154 passenger liner built in 1983, last underwent repairs in December 2014 and had since been fully serviced. As of late Sunday afternoon, the remains of 10 passengers had been recovered.
Among the victims was Yelizaveta Glinka, known in Russia as "Doctor Liza", who had won broad acclaim for her charity work, which included missions to the war zone in eastern Ukraine. Her foundation announced that she was accompanying a shipment of medicines for a hospital in Syria.
![In mourning: Alexandra, a friend of Alexander Razumov, a member of the choir, cries.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/t/e/x/image.related.articleLeadwide.620x349.gthrqd.png/1482750667744.jpg)
"War is hell on Earth, but we are convinced that good will conquer because it is stronger than any weapon," Glinka was shown saying at a recent ceremony replayed on Russian state television.
The Defence Ministry published on its website a list of passengers, who included members of the famed Alexandrov Ensemble, better known internationally as the Red Army Choir, heading to Syria to entertain troops for the coming New Year holiday.
![A woman lays flowers at the well-known military choir's building in Moscow.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/t/e/y/image.related.articleLeadwide.620x349.gthrqd.png/1482750667744.jpg)
In May, the Russian military flew a symphony orchestra led by one of its best known conductors, Valery Gergiev, to Syria to mark the recapture of Palmyra. It has since fallen to Islamic State a second time.
The ensemble was founded by Alexander Alexandrov, a prominent Soviet composer and author of the music of the Russian anthem, and his grandson Yevgeny told Meduza, a Russian news website, that "the best members of the ensemble died".
![This photo taken in 2015 shows the Tu-154 plane that is believed to have crashed.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/t/5/s/image.related.articleLeadwide.620x349.gthrqd.png/1482750667744.jpg)
"All the best soloists, the whole choir," he said. "Everything will collapse now. The best ones are gone."
Nine Russian journalists were also among the passengers.
![More than 60 members of a famed Russian choir were travelling on the Syria-bound plane that crashed in the Black Sea.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/s/x/v/image.related.articleLeadwide.620x349.gthrqd.png/1482750667744.jpg)
US ambassador John Tefft joined other diplomats and international leaders in offering condolences.
The Tu-154 is a Soviet-built, three-engine airliner designed in the late 1960s that was the workhouse of the Soviet, and later Russian, fleet of intermediate range passenger jets. In recent years, Russian airlines have replaced the jets with modern aircraft – often manufactured by Boeing or Airbus – but the military and some other government agencies in Russia have continued to use them.
![Russian journalist Dmitrii Runkov was among those killed.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/t/5/r/image.related.articleLeadwide.620x349.gthrqd.png/1482750667744.jpg)
Russia's minister for industry and trade said on Sunday that it was too early to make a decision about whether to take the jets out of service.
"There are a lot of aircraft in the world that are no longer being produced but are still being flown," said the official, Denis Manturov.
![Russian President Vladimir Putin has declared a nationwide day of mourning for victims of the crash.](/web/20161226122225im_/http://www.smh.com.au/content/dam/images/g/t/h/t/e/v/image.related.articleLeadNarrow.300x0.gthrqd.png/1482750667744.jpg)
"First we need to finish the investigation and understand the reasons (for the crash), and then make decisions."
AP, Washington Post, New York Times