More people may be buried in the rubble of a collapsed roof that killed at least 63 people last weekend in Poland's deadliest construction accident, prosecutors said today.
The prosecutors are investigating if human error or neglect led to the roof caving in during an international show of racing pigeons in a modern, football pitch-sized exhibition hall in the southern city of Chorzow.
The tragedy, which triggered three days of national mourning ending today, injured 140 and killed eight foreigners.
"It's difficult to assess how many people were in the building at the time of the accident, so there are fears that some of the presumed missing may still be buried under the collapsed roof," Tomasz Tadla, spokesman for the prosecutors' office in Katowice near Chorzow, told journalists.
After calling off the rescue operation, trained dogs were brought in to sniff out where the missing people could be buried under the huge roof. But they proved ineffective because low temperatures froze any remaining bodies, rescuers said.
The authorities delayed moving in heavy machinery today, opting to search under the roof with special cameras.
The accident is believed to have been triggered by the weight of snow on the roof and could have been compounded by potential structural weakness or bad building maintenance.
One of the building's designers, whose name has not been made public, tried to commit suicide after the accident.
"He left a farewell note but we cannot say anything more right now, other than that the case is closely related to the Chorzow disaster," Tadla told a news conference.
Tadla said representatives of building co-owner and operator MTK, a unit of Expomedia, will also be questioned in the inquiry. MTK representatives said they would cooperate with the investigation and that the roof was regularly cleared.
This week the authorities showed chunks of ice as thick as 10 centimetres, which they said were taken from the collapsed metal roof of the six-year-old building.