STOCKHOLM, Sweden - Swedish geologists have found fossilized feces from a worm that lived some 500 million years ago, media reports said Wednesday.

The tiny piles of feces were found embedded in rock-face near Malmo in southern Sweden by geologists Mats Eriksson and Fredrik Terfelt, newspaper Sydsvenskan reported.

Eriksson told the newspaper they examined the level of phosphorus of the samples and that "we realized pretty soon that it could not be anything other than coprolites, in other words fossilized dung."

Terfelt described the find as "unique."

"Cambrian scientists will certainly find them very interesting," Terfelt said.

The two are researching geology at Lund University in southern Sweden, and said they are working on an article about the find that will be published in an international magazine shortly.

"It is inevitable to joke about this, so we gave it the title 'Anomalous faces and ancient feces,'" Eriksson said.