Civilians working for the police are being put at risk by driving vehicles with official force markings, a union claims.

Wiltshire Police is in dispute with Unison over a policy of giving forensic officers' vehicles official markings.

The union says the civilian workers, who attend scenes-of-crime but do not patrol on the beat, will be exposed to the risks front-line officers face.

It says, however, those employees will not have the protection of equipment such as stab-proof vests or batons.

Scenes of crime officers often have to work alone, at night in some less salubrious areas

Chris Cahill, Unison

Wiltshire Police says the scheme will increase visibility, deter criminals and reassure the public.

Chris Cahill, branch chairman of Unison at Wiltshire Constabulary said the two-year disagreement between the two organisations had now come to a head.

"Scenes of crime officers often have to work alone, at night in some less salubrious areas, where police are not always made very welcome.

'No problems'

"And people do not always want a marked police vehicle outside their house."

Wiltshire Police said other support staff such as mechanics and education officers had used marked vehicles with no problems.

Assistant Chief Constable Stephen Long said: "Unison made their concerns known in August and we responded to those concerns.

"A full health and safety risk assessment was carried out prior to the decision being made and the policy to mark scenes-of-crime vehicles is in accordance with the force policy of marking almost all of the fleet."