Signs alerting motorists to unmarked police cars operating on a dangerous stretch of road in Sussex were unveiled today.

Sussex Police said the initiative has been prompted by the deaths of 23 people on the A23 in the past three years.

Police patrol the road 24 hours a day but, as part of a renewed effort to cut the number of deaths, the force has bought three unmarked cars.

Signs stating "police unmarked cars operating" will alert drivers to the scheme, which is the first of its kind in England.