At least nine people died when a five-story apartment building collapsed in the eastern Belgian city of Liege, police said Thursday, as rescue efforts continued. The building collapsed Wednesday after an explosion, and rescuers feared further victims were buried under the rubble, Belgian media reports said. Resident families said earlier they were still missing loved ones and some of the at least 20 injured were in critical condition, dpa reported. The explosion, believed to have been caused by a gas leak, occurred about 1:45 am (0045 GMT) Wednesday. It remained unclear how many people were in the building at the time of the collapse, police were quoted as saying. After the explosion, the 100-year-old building teetered for another five hours, then collapsed to the ground. A woman and a 12-year-old girl were rescued alive after several hours and taken to hospital suffering from shock, the fire department said.