An oily substance covering a 2-square-km strip was found floating on the sea off the coast of Qingdao where the Olympic sailing events are being held, the city government said on Tuesday.

The unidentified substance was first reported by the city maritime department on Monday evening, said Wang Weiping, deputy secretary general of the city government.

The substance has remained on the surface of the sea, about 30 nautical miles from the Olympic sailing event area of Shandong Province, since Monday evening.

"We think it will not affect the sailing events as oil film is usually emulsified in a few days and the north wind will blow it southward and away from the competition area," Wang said.

The department was still investigating the cause, he said.

(Xinhua News Agency August 12, 2008)