HARBIN, Nov. 22 (Xinhuanet) -- The provincial health department of northeast China's Heilongjiang province vowed Tuesday to step up inspection of water quality as a chemical plant blast caused possible water contamination in Harbin, capital of the province.

    Harbin announced on Monday to stop water supply for four days as of Tuesday evening for fears that a chemical plant blast on November 13 may have caused a leakage of poisonous substances into the Songhua River, a major water source of the city.

    Harbin is located at the middle reaches of the river, which originates in the neighboring province of Jilin. The blast took place in the chemical plant only a few hundred meters upstream.

    The announcement has sparked frenzied purchase of drinking water in the city with a population of 3 million. Bottled water, various beverages and even boxed milk were sold out by Tuesday morning in some supermarkets and food stores.

    The local health department ruled that drinking water in the city has to be checked twice every day, to ensure the water quality drinkable.

    Severe measures will be taken simultaneously in all water-related enterprises and companies to abide by the standards of the safe water quality. Enditem