Investigators have found the black boxes from a Russian airliner which plummeted into a field in Ukraine with 170 people on board after flying into a severe thunderstorm.

Distraught relatives, some barely able to stand, were being flown to the crash site from St. Petersburg, where the Tu-154 had been heading on a flight from a Black Sea resort on Tuesday.

There were no survivors after the aircraft operated by one of Russia's largest carriers, Pulkovo Airlines, exploded in a ball of flame.

Officials initially said the plane had probably been hit by lightning, but investigators warned against drawing premature conclusions.

Russian Transport Minister Igor Levitin, head of a government commission investigating the crash, told Russia media yesterday that search teams had recovered the key data and voice recorders, the so-called black boxes.

Flight 612 was flying from Anapa back to its St. Petersburg home base. Russian television said the aircraft had received authorization to fly across Ukraine's eastern tip, where it encountered a thunderstorm.

Russian and Ukrainian search teams, numbering up to 400 workers, divided the crash area into squares. Workers wearing white gloves put bodies in black plastic bags and loaded them on to stretchers for removal from the scene.

Russia's NTV television said 130 bodies had been recovered so far.

Russian television had showed a film clip taken in the village about 45 kilometres north of Donetsk showing a ball of flame rearing up in the distance along with a vast cloud of smoke.

"We all heard a loud rumble and I turned to see the plane beginning to fall... It hung in the air and then began to hurtle towards the ground. It all lasted about 10 seconds," Yevgeny Donets, in his early 20s, told First Channel.

"We ran to the scene, but you could hardly see for the downpour. Everyone was dead. We made our way through the marshes. There was a big fire and a lot of smoke."

News reports said the dispersal of debris over an area the size of a soccer field ruled out a mid-air explosion. But the head of a rescue team at the site, Vadim Seryogin, told Russian television it was too early to make conclusions.

In St. Petersburg, Vasily Nalyotenko, deputy head of Pulkovo Airlines, said relatives would leave for the crash site only in the evening to accommodate families living outside the city.

Nalyotenko said passenger lists showed two Germans, a Dutch national, a French citizen and one Finn among the casualties. Most of the dead, including 45 children, had been spending summer holidays on the Black Sea coast.

(China Daily August 24, 2006)