Workers were racing Thursday to retrieve the 3,000 chemical-filled barrels that were swept by floods into the Songhua River in northeast China's Jilin Province.

Each barrel contained 170 kilograms of chemicals, officials said at a press conference Thursday. Another 4,000 empty barrels also entered the Songhua River.

But no chemicals had been detected in the river water, Ministry of Environmental Protection spokesman Tao Detian said Thursday.

Emergency workers on rubber dinghies Thursday were using poles and steel nets to collect floating barrels at a port in Yushu City, on the lower reaches of the Songhua River. Three cranes and two fire trucks were parked on the riverbank.

More than 470 barrels had been retrieved in Yushu and were properly stored in tents, Chen Rongju, head of the city's work safety watchdog, said.

The barrels tumbled into the Wende River on Wednesday and then floated into the Songhua River after floods broke storage facilities of two chemical factories -- Jilin Xinyaqiang Biochem Co. Ltd. and Jilin Zhongxin Group -- in Jilin City.

Of the 3,000 chemical-filled barrels, about 2,500 barrels contained trimethyl chloro silicane -- a colorless flammable liquid -- while 500 contained hexamethyl disilazane, a colorless liquid, officials said.

Both chemicals had a pungent odor.

Workers are collecting the barrels at eight points on the river and officials vowed to stop the barrels from entering neighboring Heilongjiang Province on the 1,900-km long Songhua River.

The river, the largest tributary of the Heilongjiang River, which lies between China and Russia, is the drinking water source for cities in Jilin and Heilongjiang.

Tap water supplies were stopped in Jilin City late Wednesday, but local officials said it is a technical suspension not linked to the accident.

By early Thursday afternoon, the water supply had not resumed.

Environment workers are monitoring the water quality at seven stations around the clock.

But panicked residents in Harbin, capital of Heilongjiang Province, have started to store water, pushing up the market prices of bottled mineral water.

A chemical spill contaminated the Songhua River in November 2005 after an explosion at a petrochemical plant. Water supplies for 3.8 million people in Harbin were cut for five days.

(Xinhua News Agency July 29, 2010)