Beijing, China (Reuters): At least nine people were killed while other six injured as an explosion ripped through in northern China 's Shanxi province on Saturday evening, state news agency Xinhua reported.

The blast occurred in a residential building and was believed to have been caused by illegally stored explosives, Xinhua said. An investigation was underway

A number of buildings collapsed and search and rescue work continued on Sunday afternoon, said state broadcaster CCTV.

China has a poor record of industrial explosive accidents in residential areas.

In October, 14 people were killed in neighboring Shaanxi province when a blast caused by illegally stored explosives destroyed a block of prefabricated houses.

A province-wide investigation into explosive production and storage was launched following the incident.

Both Shanxi and Shaanxi have large coal mining industries, where explosives are regularly used.