The cause of the factory fire that killed 15 people in south China's Shenzhen City was confirmed to be the combustible material piled there catching fire, said local police on Thursday.

The blaze broke out early Wednesday?on the first floor of a foam recycling station of Shenzhen Longfei Recycle Materials Co. Ltd in the Shannan District, the city press office said.

The fire killed 15 people and severely injured three others. The three injured people, all in stable conditions, were receiving treatment in hospital, said a spokesman of the office.

According to investigation, the company set up a loft over piles of collected foam material that was easy to catch fire.

The people in charge of the company were now under police investigation.

The 15 victims have been identified, eight from Lufeng City of Guangdong Province and seven from Fengjie County from southwestern Chongqing Municipality.

The district government set up 14 working teams dealing with the aftermath.

Work safety authorities have carried out a thorough inspection over the factories in the city to prevent further safety hazards.

(Xinhua News Agency February 29, 2008)