A ship carrying 130 tons of liquid caustic soda was sinking on the Yangtze River, risking polluting the river with the corrosive chemical, said a local government official on Friday.

The ship, "Xianghan Shouwei 0298", was set to sail to neighboring Hunan Province with 500 tons of liquid caustic soda from Zhicheng Harbor in Yidu City, on the middle reaches of the Yangtze River, said Xu Changming, a spokesman of Yidu government.

However, workers found water leaking into the ship around 7 a.m. on Friday when they had loaded 130 tons of the chemical.

The chemical was sealed inside the ship and no leakage has been reported, though half the ship is now under water, Xu said.

The city environment bureau had sent investigators to the scene, who were testing the water quality every 30 minutes. The water is so far unpolluted.

Rescue ships were coming to the pier from Zhicheng Harbor from two kilometers away. But they were hampered by poor visibility caused by thick fog, said Wu Lin, head of the maritime office of Yidu government.

Liquid caustic soda, with a concentration of 32 percent, is listed as a dangerous chemical, and it is feared its leakage may pollute the river.

(Xinhua News Agency December 14, 2007)