Tuesday's explosion at a chemical plant in South China's Guangxi Zhuang Autonomous Region caused no pollution to air or water, authorities said.

The regional Department of Environmental Protection said that samples taken after the explosion ripped through an organic compound workshop inside the plant, owned by Guangxi Guangwei Chemical Co., at 6 a.m. on Tuesday, showed no pollution.

The blast at the workshop led to further explosions in containers storing flammable substances such as formaldehyde, acetylene.

At least 16 people were killed, and six others are missing, while 57 were injured, the rescue headquarters said.

Fourteen of the dead were workers at the plant, while the other two have yet to be identified, the headquarters said.

The explosions persisted until almost 1 p.m.Tuesday. The fire spread over 10,000 sq m, said a firefighter who took part in the rescue operation. The blaze was put out by Tuesday evening. Firefighters were still searching for the missing in the debris.

About 11,500 people, living within 3 km of the plant were evacuated.

More than 100 chemical emergency specialists were dispatched to the site to assess the safety situation. Regional work safety authorities are investigating.

The plant mainly produces polyvinyl acetate (PVA), which is used in adhesives, calcium carbide, and vinyl acetate monomer (VAM), which is used in paints, adhesives and coatings.

The plant is in a development zone of Yizhou City, a four-hour drive from the regional capital of Nanning.

With assets of 340 million yuan (50 million U.S. dollars), the plant manufactures products worth about 300 million yuan a year, and its largest shareholders are state-owned companies.

(Xinhua News Agency August 27, 2008)