Six died and four others were injured after firecrackers exploded in an illegal production plant in north China's Hebei Province, Xinhua quoted authorities as saying. The blast occurred at around 5:08 p.m. Saturday in a house in Guzhuangying Village, Xushui County, the county government said. Five died at the scene and one died while being transferred to a hospital in Baoding City. Four were hospitalized. Witnesses said they heard a big bang and then saw a cloud of dark smoke rising. The blast destroyed the roof of the house and shattered window glasses of nearby houses. Police said an investigation showed the owner of the house was illegally producing firecrackers.