The officers used a taxi to travel round areas of Colne where Asian drivers had been verbally abused, punched and had stones thrown at their cars.

Hot spot areas were targeted, including the North Valley "corridor" and retail park, Vivary Way and the town centre where three Asian taxi drivers and a cab base were attacked.

Sending out plain clothed officers to pose as customers and drivers of cabs worked to stop a similar outbreak of attacks last year.

Sgt Fryer said: "We'll be continuing to use the taxi for the next couple of weeks concentrating on these hot spots where the incidents have happened before to clamp down on these types of incidents."