Police patrol cars are being replaced by speed cameras because of cost, it was claimed last night.
Concerns were raised after research revealed cameras outnumbered cars in parts of the West Midlands by more than seven to one - the highest national ratio.
Staffordshire has 35 cars and 260 cameras - one to 7.4, according to a study carried out by Auto Express magazine.
London's Metropolitan and City of London police forces have 140 cars and 828 cameras - one to 5.9.
Warwickshire has the same number of cameras and cars - 27.
A spokesman for the West Midlands Police Casualty Reduction Partnership, whose cameras raised #2.88 million in the last financial year, said the simple reason was cost.
"It costs #12,000 to install a camera and a patrol vehicle costs #20,000 to #30,000 and a police officer around #35,000.
"Obviously an officer can monitor different things, but one of them is cheaper."
In the West Midlands there are 235 cameras and 82 cars, while the West Mercia force has 29 cameras and 22 cars.
The magazine also found areas such as Durham, Dumfries and Galloway, North Yorkshire, Central Scotland and Northern Scotland had no cameras.
Auto Express editor-in-chief David Johns said: "There's been plenty of anecdotal evidence officers are being replaced with cameras, and now we have the proof. It's a really worrying situation for honest motorists because Gatsos and other traps can do nothing to tackle more serious crimes."
Using the information from forces, Auto Express also said which were the most popular cars used by the traffic police .
The top three were all prestige while 60 per cent of the cars used were from luxury brands such as BMW, Mercedes and Volvo.
Mr Johns said: "Maybe if some forces bought less expensive makes they could afford to have more traffic cars and therefore wouldn't have to rely so heavily on speed cameras.