Londoners have paid £7.3m in fines in one year after being caught out by CCTV cars which "compromise road safety", a privacy campaign group has claimed.
Currently 24 councils use cars mounted with cameras on masts to spot traffic offences, Big Brother Watch said.
The group said these patrol cars were being used by councils to "make money, with road safety only an afterthought".
Lambeth Council, which earned the most at £1.68m, in fines, said its income went towards road safety schemes.
Big Brother Watch said it obtained these figures from councils under a Freedom of Information request.
Councils issued the fines to 161,000 London motorists between April 2009 and March 2010.
Across Britain, 31 councils use the patrol cars and 25 of these issued fines worth £8m using these vehicles, the campaign group said.
Up to March, Lambeth Council fined 34,016 motorists, followed by Havering Council where 18,602 drivers paid £923,331 and Westminster Council where 14,217 motorists were issued with fines worth £725,851.
London has 45 CCTV cars in operation, with Waltham Forest, Camden and Bexley councils each having four of these vehicles, the highest number in the capital.
Dylan Sharpe, campaign director of Big Brother Watch, said: "The CCTV Smart car represents a very dangerous escalation in Britain's surveillance society.
"The vehicles are sent out to catch people and make money, with road safety only an afterthought.
"It is surely only a matter of time before more councils start using these cars."
A Lambeth council spokesman said: "Lambeth is one of the busiest parts of London and our residents expect us to keep our roads safe and clear of congestion.
"Parking enforcement is categorically not about raising money, it is about keeping roads safe and clear.
"Any surplus income goes directly towards schemes that make the our roads safer, such as 20 mph zones and cycle lanes, as well as funding Freedom Passes for older people."