Authorities around Poland ordered the roofs of hundreds of buildings cleared of snow and ice, as the death toll from the collapse of an exhibition hall rose to 64 after search dogs found two more bodies Tuesday.

The rescue dogs detected the bodies during a final sweep ahead of a planned removal of the wreckage of the exhibition hall in southern Poland, said Krzysztof Mejer, a spokesman for the regional government.

About 500 people were estimated to be in the hall for a pigeon racing exhibition when the roof gave way Saturday, apparently under the weight of the heavy, icy snow. Some 160 people were injured, 82 of whom remained hospitalized Tuesday, Mejer said.

Interior Minister Ludwik Dorn said authorities were looking into allegations in several newspapers that the roof of the 6-year-old building caved in before, during an event in 2002. The allegations were made by former employees of the company that organized the fair.

"All that still must be investigated — whether the roof caved in, what the owners' reaction was, whether construction authorities knew about it," Dorn said on state radio.

About 200 people, meanwhile, were evacuated from a Polish supermarket late Monday when its roof appeared to bend under the weight of snow. But experts checked the British-owned Tesco supermarket in the central city of Lodz and determined there was no danger, spokesman Wojciech Sokol said.