Engineers have said they do not know what caused a blackout in west Oxfordshire.

Thousands of people were without electricity from 7pm to midnight on December 10 after a power cut hit villages near Chipping Norton, including Charlbury, Chadlington and Spelsbury.

A Southern Electric spokesman said the failure was due to an underground fault, but the company did not know what had caused it.

About 400 homes were affected by the blackout.

Workers fixed the problem by switching the electrical supply to a different circuit.

The spokesman added: "We will be investigating and carrying out repairs.

"We apologise to our customers."