The West Yorkshire Police vehicle was on an emergency call when it was in collision with a Mercedes C180 car at the junction of the Headrow and Calverley Street.

Six people, including two police officers, suffered minor injuries. Three of those needed hospital treatment and were discharged. The injured included at least one pedestrian and the 30-year-old driver of the Mercedes.

A spokesman for West Yorkshire Police said an internal investigation was being carried out into the incident, which happened at about 6pm on Monday. Witnesses are asked to contact road traffic officers at the force's City and Holbeck division on 0113 241 4642.

The crash happened less than three months after another police vehicle smash on the Headrow. It took place near to Vicar Lane in the early hours of June 4, reportedly during a car chase.

Figures released last year showed that West Yorkshire Police officers were involved in 18 work-related crashes between April 2004 and September 2006.

Those incidents claimed 10 lives — the joint second highest total behind the Metropolitan Police.

National figures released at the same time prompted a warning that police drivers were taking "unnecessary risks" in high-speed chases.

Nick Hardwick, chairman of the Independent Police Complaints Commission, said: "Policing and police driving is a high-risk activity. We are not saying don't take the risks. We are saying understand them and manage them properly."

Read our hour of live webchat with the Boot Room's Andrew Hutchinson to find out what fans thought about Leeds United's thrashing of Crystal Palace and their forthcoming fixtures against Bristol Rovers and Bradford City.

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