Russia has begun the grim task of identifying the victims of FlyDubai flight FZ981, which crashed during bad weather at Rostov-on-Don airport, killing all 62 people on board.

Emergency workers on Sunday finished combing the debris-laden runway after the Boeing 737-800 from Dubai nosedived and exploded in a giant fireball after trying to land for a second time in strong winds.

The plane was carrying 55 passengers and seven crew when it crashed at 3:40am Saturday local time (11:40pm AEDT). Four children were among those killed.

No Australians were among the dead on the airliner, which reportedly plummeted 3000 feet in just 15 seconds.

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Flydubai promised to carry out a swift investigation into what happened but CEO Ghaith al-Ghaith said it was “too early” to determine the cause.

Russia’s Investigative Committee said poor conditions, pilot error or a technical failure may have been responsible for the crash.

Several factors may have been to blame for the crash.

Several planes had trouble landing at the airport at the time of the crash, with one trying to land three times before giving up and diverting to another airport, experts said.

Hundreds of people flocked on Sunday to the airport, the region’s largest, to lay flowers and leave candles and toys in memory of the dead.

The city is 950 kilometres south of Moscow near the Ukrainian border.

State-owned Rossiya-24 on Sunday interviewed a mourner living nearby who said she was woken by the sound of the explosion.

“The housed started shaking. I looked out of the window: the sky was red and in a few seconds it was over,” said the woman, whom Rossiya did not identify.

Closed-circuit TV footage showed the plane going down at a steep angle and exploding.

The footage appears to show the plane on fire before it hits the ground.

The powerful blast left a big crater in the runway and pulverised the plane.

The plane’s two black boxes – its cockpit voice and flight data recorders – have been taken to Moscow for examination but could take up to a month to decode.

“The received recorders are badly damaged mechanically,” Russia’s Interstate Aviation Committee (IAC) said in a statement on its website.

“Specialists … have started the inspection, opening and removing the memory modules from their protective coverings for further work to restore the cable connections and prepare to copy the data.”

Identifying victims ‘could take months’

Southern Regional Emergency Centre head Igor Oder said emergency crews had recovered human remains, but identification could take months.

Services to commemorate the victims are being held across Russia. Photo: Getty

The Rostov Emergency Ministry said the plane’s wing hit the ground, but Russian news agencies cited a source in the emergency services saying that the plane fell vertically and hit the ground on its nose.

Mr Ghaith said he had no information to indicate the pilot had issued a distress call.

Both the pilot and co-pilot had over 5000 hours of flight experience each, he said.

There was one Russian among the seven-person crew, the Russian emergency ministry said in a statement.

The pilot was Cypriot, the co-pilot and another crew member Spanish and the other three were from Seychelles, Colombia and Kyrgyzstan.

FlyDubai said in a statement there were 44 Russians among the 55 passengers, eight Ukrainians, two Indians and one Uzbek.

Russian Transport Minister Maxim Sokolov said the airport would reopen on Monday morning.

-with AAP and ABC