More than 50,000 residents from the southern German city of Augsburg are being evacuated from their homes so that an operation to defuse a World War Two bomb can get under way on Sunday.

It is the country's biggest evacuation for an unexploded bomb since the end of the war.

The 1.8-tonne British explosive is thought to have come from a 1944 air raid, which destroyed the old town.

It was uncovered during construction work.

Police say they do not know how long the operation will take.

The BBC's Europe regional editor Mike Sanders said the city authorities are taking no chances, and are evacuating everyone with a 1.5km (0.6 mile) radius of the bomb.

The authorities are confident that most people affected can stay with friends or family, but a number of schools and sports halls have been opened as shelters for those in need.

Most Germans celebrating Christmas open their presents and have their main festive meal on 24 December, rather than Christmas Day.