An explosion that occurred on Thursday afternoon at a factory in Wuji county of Shijiazhuang, North China's Hebei province, killed seven people and wounded one as of Friday, Xinhua News Agency reported.

The factory, named Tianzexin Pearl Cotton Factory, produced pearl cotton (polyethylene foamed cotton, a kind of packing materials) and related products, which are flammable.

Located near Shicun village at Beisu town, the blast took place at around 6 pm on Thursday. The blast caused a fire which was put out later, according to an official announcement by the publicity department of Wuji county.

On-site search and rescue work has ended. Persons related to the incident have been summoned by public security authorities. Investigation on the cause of the blast is underway.