About 100 tons of dangerous chemicals equivalent to 10 tanker-truck loads was spewed into the Songhua River, which supplies water to Harbin, the nation's environment watchdog disclosed yesterday.

Zhang Lijun, vice-minister of the State Environmental Protection Administration (SEPA), told a press conference in Beijing that Jilin Petrochemical Corporation, a subsidiary of China National Petroleum Corporation (CNPC), "should be responsible" for the leak of benzene and its derivatives following an explosion at a chemical plant.

The plant, on the upper reaches of the river in Jilin Province, earlier denied any connection between the contaminated water and the explosion on November 13, which left a trail of dead fish.

But Jilin Vice-Governor Jiao Zhengzhong, also Party secretary of Jilin city, apologized to the 3.8 million residents of Harbin on Wednesday during a visit there. He brought 71 tons of mineral water with him. "We will work with the Heilongjiang provincial government to quickly investigate the incident," Jiao said.

CNPC also apologized to Heilongjiang people yesterday.

Water supply has been suspended in Harbin since Tuesday midnight and the city government is keeping a close watch on an 80-kilometre swathe of polluted water in the Songhua which flowed into the city early yesterday morning.

"We know where the toxic water is and how its density changes," said Li Weixiang, director of the Heilongjiang Provincial Environment Protection Bureau.

The slick, flowing at about 2 kilometres an hour, is expected to pass the city by Saturday morning.

The Harbin Water Purification Plant said it could restart water supply on Sunday, Xinhua reported.

Heilongjiang Governor Zhang Zuoji earlier vowed to "drink the first mouthful of water once the supply is resumed" to ease people's worry about water quality.

On the second day of the water-supply suspension, Harbin residents found it much easier to buy bottled water, which was readily available in shops and supermarkets.

"Now it is totally unnecessary to worry about buying water," said Teng Song, a postgraduate student of Harbin Institute of Technology.

The city has drilled 55 wells in three days, and more will be dug, the government said on its website.

But many people still chose to leave the city.

For the fourth day in a row, sales of air and rail tickets remained brisk as many were sending the elderly and the young to other places.

A saleswoman in Harbin North Ticket Centre, one of the largest in the city, told China Daily there was strong demand with tickets to Guangzhou and Shanghai sold out for yesterday.

Liu Yunlong, a businessman, said he would send his two sons to Shenyang, capital of Northeast China's Liaoning Province. "I can't afford to let anything happen to my children," he said.

On the international front, China has informed Russia of the situation in the Songhua River which flows into the neighbouring country Foreign Ministry spokesman Liu Jianchao told a press briefing in Beijing yesterday.

"China attaches great importance to the potential impact and harm caused by the pollution on Russia," he said, adding that Russia appreciated the information.

The Songhua is a tributary of the Heilong River (called Amur River in Russia).

Source: China Daily