Tests show that chemical-tainted waters of a major northeast China river has flowed into Heilongjiang Province from Jilin where some 7,000 chemical barrels were initially swept into the river by floods last Wednesday, a senior local official said Sunday.

Chemical buckets have polluted the water after floods washed them into the Songhuajiang River last Wednesday in Jilin Provence. [Xinhua]

Chemical-tainted water was found at Guqia Port, Zhaoyuan City, on the Songhua River near the Heilongjiang Province-Jilin Province border.

The tainted water first flowed into Heilongjiang at 7 p.m. Saturday, Du Jiahao, executive vice governor of Heilongjiang, told reporters Sunday.

Tests conducted in Zhaoyuan have found "a minimal amount of certain chemicals," indicating that tainted water has arrived in Heilongjiang, Du said.

The provincial government's environmental watchdog will enhance monitoring and timely publicize test results to avoid "unnecessary public panic," he added.

Ministry of Environmental Protection tests show the river's water quality "within a normal range," ministry spokesman Tao Detian told Xinhua Sunday.

Tests conducted in Jilin have already shown "a very small quantity" of hexamethyl disiloxane in the water.

Local environmental specialists said the level of chemicals in the water "poses no threat" to public health and that the environmental impact of the accident is "negligible."

Water quality tests in Jilin showed the pH reading in the river is within a normal range.

Some 3,000 chemical-filled barrels and 4,000 empty barrels were swept into the Songhua River Wednesday morning after floods hit the warehouses of two chemical companies in Jilin City, Jilin Province.

Each chemical-filled barrel contains about 170 kilograms of either trimethyl chloro silicane or hexamethyl disilazane.

Workers had retrieved 5,365 barrels - some filled, some empty - by 9:30 a.m. Sunday.

Hundreds of soldiers, armed police and firemen are stationed at Guqia Port to intercept the barrels.

Boats are chained together across the 500-meter wide waterway to block the passage of the barrels.

Emergency workers have also prepared a 400-meter-long oil spill boom to to contain any contaminated water.