GREEN campaigners called police after discovering an illegal logging site in a nature reserve – only to find the culprits were a gang of beavers.

Environmentalists found 20 neatly stacked tree trunks and others marked with notches for felling at a beauty-spot in Subkowy, northern Poland.

But when officers followed a trail left by a tree which had been dragged away, they found a beaver dam right across the river as reported by the Austrian Times.

A police spokesman said: "The campaigners are feeling pretty stupid. There's nothing more natural than a beaver."