The number of drivers being caught speeding has soared by more than half a million during the past six years as cash strapped police forces increasingly resort to roadside cameras to raise revenue.

Last year 2,292,536 motorists - equating to four every minute - were detected breaking the speed limit on Britain's roads.

That figure is up a third on the same period six years ago when just over 1.7 million drivers were caught going too fast.

The sharp rise has been put down to the continued roll out of speed cameras across the country's road network.

In some force areas the number of drivers flashed for speeding has soared by more than 400 per cent.

Around half of those who are caught now pay to attend a speed awareness course rather than opting to accept points on their licence.

It is estimated that around a quarter of all British drivers have now been on a speed awareness course, and the schemes are believed to generate around £50 million annually for police forces.

While constabularies are not supposed to profit from the courses they are able to recoup a maximum of £45 per driver to cover administration costs.