The concave, snow-covered roof of a Moscow market collapsed early Thursday, killing at least 31 people and trapping about 10, officials said.
Rescue workers used metal cutters and hydraulic lifters to clear the ruins of steel and concrete pieces. Workers used pickaxes to cut holes in the wreckage and knelt to call into the holes in search of survivors.
Mayor Yuri Luzhkov, who went to the site to oversee rescue efforts, said terrorism was unlikely. "Chances are more than 90 percent that a terrorist act can be ruled out," he told reporters. "It was a technical accident."
Twenty-five people were injured and most of them were hospitalized, emergency officials said.
Medical workers inserted an intravenous drip to administer painkillers and other medications to a man trapped under a slab of concrete that left only his hand visible. Rescuers used heat guns to blow warm air into the rubble to try to prevent victims from succumbing to near freezing temperatures.
Trapped survivors were using mobile phones to call their relatives, helping rescuers zero in on their location, said Yuri Akimov, deputy head of the Moscow department of the Emergency Situations Ministry.
The victims were municipal and market workers, and Mayor Yuri Luzhkov said all the dead were guest workers from outside Moscow. Channel One said they had spent the night in the Bauman Market, which was not open for retail business. Ekho Moskvy radio reported that there could also have been wholesale buyers in the building.
No sounds could be heard from beneath the rubble though sniffer dogs indicated there were still survivors there, Emergency Situations Ministry spokesman Viktor Beltsov told reporters.
"There may be people alive under there but time is passing," Beltsov said, adding that many panels had fallen on top of one another "so it would be hard for a person to be (alive) in there." He said 31 people had been confirmed dead by early afternoon.
Earlier, Emergency Situations Minister Sergei Shoigu told reporters that trapped survivors could be heard "knocking and crying out."
Investigators were looking at three possible causes of the collapse: improper maintenance of the building, a build up of snow and errors in the building's design, Moscow prosecutor Anatoly Zuyev said, reports the AP.
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