Nuisance riders were issued with warnings about losing their bikes

An operation to tackle the growing problem of off-road motorcycling was carried out by police on Sunday.

The force receives hundreds of calls a month from members of the public complaining about off-road motorbikes on common land or school fields.

Offenders were told they could face prosecution if they ignored warnings.

A police helicopter was used to spot nuisance riders and inform officers on bikes about locations used by offenders.