The supermarket, in the town of Bytom, a few kilometers (miles) outside Chorzow, was cleared of customers and closed down at around 6:00 pm (1700 GMT), after an inspection showed one of its walls to be fissured, Poland's PAP news agency reported.

The shop's roof was then cleared of snow.

Firemen in Bytom said that, although the fissure in the supermarket's wall was not recent, it could still pose a risk to clients.

Polish Interior Minister Ludwik Dorn ordered Sunday that all large public buildings should be inspected and their roofs cleared of snow after the preliminary findings of a probe into the Chorzow tragedy, in which at least 66 people died and 141 were injured, indicated that the roof of the town's exhibition hall probably collapsed under the weight of accumulated snow.

"I have ordered immediate checks of all large buildings, in particular supermarkets and swimming pools, around the country," Dorn told a press conference in Warsaw earlier Sunday.