It is a bit of an alien site on one of our region's rivers.

Last night saw the coldest temperatures of the winter so far for England, down to -8 in some parts, and the falling mercury created an unusual phenomenon.

Ice pancakes, each about the size of a dinner plate, have been spotted on the on the River Irthing near Gilsland.

Joan Thirlaway was lucky to spot them and sent in these pictures.

These icy circles normally form in rough seas around the Arctic and Antarctic but, when temperatures fall low enough, they can form in some rivers.

It is thought the strange circular site happens when bits of foam on the water start to freeze and bump into each other.

Temperatures need to be well below freezing Credit: Joan Thirlaway