Temperatures will continue to plunge, weather forecasters have warned, as Britain battles the big chill.

The mercury dropped to as low as minus 11C (12.2F) in the early hours of Tuesday morning in Aboyne, northeast Scotland, while thermometers fell to minus 10C (14F) in Farnborough, Hampshire, and in Capel Curig, North Wales.

Tens of thousands of motorists were left stranded in a record day for car breakdowns amid chaotic scenes on the roads. The AA and RAC said the situation was worse than it had been since 2004, with an estimated 50,000 call-outs over the previous two days.

And many schools failed to reopen after the Christmas break as homes and businesses battled to repair frozen pipes and boiler problems.

Staff at Bourton-on-the-Water Primary School, in Gloucestershire, were counting the cost of the freezing weather when water from burst pipes flooded a classroom and caused the staff room ceiling to collapse.

A string of other schools - including several in West Wales, Surrey and Berkshire - were also forced to turn pupils away. And it was so cold in Allenheads, Northumberland, that the oil froze in the kerosene heated boilers used to warm many homes.

Daniel Adamson, a forecaster for MeteoGroup UK, said Wales and southern England - including London and the South Coast - could yet face its coldest period later.

He said: "It is unusual that the far south could be facing temperatures as low as minus 10C. It is probably one of the coldest days of the year."

Among the victims of perilous driving conditions was a woman cyclist who sustained serious injuries when she was run over by a Land Rover which skidded on ice in Clevedon, Somerset.

In Dorset, a man escaped injury after his BMW 325 convertible spun off the road and hit a telegraph pole near Bournemouth International Airport after 6am.

In Devon and Cornwall, police warned drivers to delay journeys after seven crashes this morning including two multi-car collisions.

And in Cumbria, police warned that children are risking their lives by playing on the ice covering one of England's largest lakes. Youngsters were seen trying to smash holes with boulders as they played on the ice 50ft from the shore on Derwentwater in the Lake District.

Meanwhile, Rosie Winterton, Minister for Pensions and the Ageing Society, said pensioners should not worry about turning the heating up as the Government has increased Winter Fuel and Cold Weather payments for the elderly.

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