Rescue boats were making slow progress in scooping up an oil slick in the southern Baltic Sea that was drifting towards Germany on Wednesday because the oil was thicker than expected,
coastguards said.
The origin of the slick was unknown, but was likely to be a spill from a ship passing through the busy area.
The slick was 17 miles long and 250 m wide when discovered about 45 km south of the port city of Ystad on Sweden's southeast coast around noon on Tuesday.
The Swedish Coast Guard said in a statement that a Swedish and a German ship had managed to scoop up only about 212 cu. ft. (six cu. m) of oil between them as the slick drifted into Danish and German territorial waters. It was reported that five other ships were on the scene and one more, from Denmark, was en route.