RARE 'ice pancakes' form on the fast flowing River Tees have been spotted in Barnard Castle, County Durham this week.

The sight was snapped on Wednesday after the 'pancakes' formed due to the sub-zero temperatures. Most frequently seen in the Baltic Sea and around Antarctica, the rare phenomenon sees pieces of foam turned into ice knock against each other as they freeze and grow, causing their edges to rounden.

Small rims are then created on the edges as the knocking causes splashing water to freeze and join the rim.

They came as motorists, cyclists and pedestrians have been urged to remain cautious after the cold snap brought ice to many parts of the country.

An overnight low of -9C was recorded in Aboyne, a village on the edge of the Highlands in Aberdeenshire and yesterday High Coniscliffe CofE Primary School, in Darlington, had to close after being left without heating or hot water.

Becky Mitchell, a Met Office meteorologist, warned people to be aware of the dangers associated with ice and said many parts of the country could see snow hit at the weekend as another cold snap draws in across the country.