Dorset Police say residents regularly complain about the noise

Dorset Police, who regularly receive complaints from residents about the noise the bikes make, launched a crackdown on them on Wednesday.

The law states riders must be over 16, have at least a provisional driving licence and wear an approved helmet.

The bikes cannot be insured or licensed for road use, police said.

'Private land'

Dave Stroud, from Dorset Police, said: "It's dangerous. It's dangerous for them (the riders) and it is dangerous for the public at large.

"They are very noisy and people are ringing the police regularly to complain about the noise.

"We treat mini-motorcycles found on a road - including pavements, footpaths and verges - like any other motorcycle and can seize any mini-motorcycles that are uninsured or ridden without a licence.

"Our poster emphasises the need for riders of mini-motorcycles to have absolute permission to ride on private land."