A powerful explosion tore through a fireworks store in south China\'s Guangxi Zhuang Province Tuesday, killing at least four people, authorities said. The blast occurred early morning in the store located in a two-story building in the province\'s Anhe city, the state-run Xinhua news agency reported. Local officials said the blast caused the store ceiling to collapse, trapping five people in the rubble. The fifth victim was undergoing emergency treatment at a local hospital, but a report on his condition was not immediately available. The cause of the explosion was being investigated, the report said.