Single mother Margaret Henderson got the shock of her life when she received an electricity bill for £36,831.

Yorkshire Electricity demanded payment in seven days in an abrupt final reminder.

Margaret, 28, of Blaydon, Tyne and Wear, rang to protest, and after an investigation it was found a computer blunder was to blame.

She said: "They even had the cheek to say someone would call to collect the money."

A spokesman for the company said: "We have apologised for any inconvenience and distress caused by our error.

"It sounds like an excuse, but there really was a computer error which was not picked up by our usual checks.

"With eight million bills going out every year, there are bound to be some mistakes.