BEIJING (AP) _ An explosion Friday at a chemicals plant in northern China killed one person and left 12 others missing, authorities said.

   Thirteen people were on a floor that produced emulsion explosives at the plant run by Kailuan Group in the city of Tangshan when the morning blast occurred, the government of Hebei province said in a statement. One person was confirmed to be dead, and authorities were searching for the 12 others.

   The brief statement gave no cause for the explosion.

   Workplace safety is a major issue in China. A shoe factory fire in the eastern city of Wenling in January killed 16 people, prompting a broad government campaign that shut down many of the city's shoe factories to ensure compliance of safety rules.

   Last June, 121 people were killed in a poultry plant fire in the country's northeast. That fire was triggered by a short circuit, but investigators found the plant's safety exits had been blocked, trapping workers inside. Several city officials were fired for failing to enforce safety regulations.