The cameras, operated by the Northamptonshire Casualty Reduction Partnership, could be replaced because of a lack of public confidence in them and concerns about their effectiveness in improving road safety.

A review group was set up last year to look at the effectiveness of the cameras and it is believed that Northamptonshire County Council is seriously considering pulling funding for them. Any such move would have to be made in conjunction with the police, who are part of the casualty reduction partnership, which has a budget of £2m a year.

The Evening Telegraph understands significant savings could be made by abandoning the cameras.

Northamptonshire County Council leader Jim Harker would not confirm any decision had been made.

But he said: "This is an area I know the public are very concerned about.

"There are benefits but also a number of issues where they are not so confident about them. We will be reviewing it over the next few weeks.

"I know there have been concerns from the public and the RAC about them. There is evidence that people tend to react quickly to cameras and slow down sharply, creating hazards and possibly accidents.

"If cameras are not there, we are already looking at a wide range of speed reduction measures. We know the public are enthusiastic about vehicle activated signage, where approaching drivers are warned about their speed and people take more notice of these."

He added: "We shall be embarking on public consultation regarding it."

A decision could be made in the next few months, with the cameras disappearing by April. Static cameras are likely to remain in use.

A group set up in 2007 to monitor the effectivness of speed cameras in Northamptonshire reported its findings to the county council earlier this year.

The study suggested the use of mobile speed cameras should continue.

Motorist Margaret Keevil, of Orchard Field in Cranford, said: "I think they should be used. If people were keeping to the speed limit, they have nothing to worry about. Accidents happen when people don't stick to the speed limit."

A spokesman for the RAC said the use of mobile speed cameras should be judged on the merits of each area where they are used.

In October, Swindon became the first UK town to scrap speed cameras because its council objected to the fines revenue going to the Government.

The revenue from speeding fines issued in the county has increased by £2.3m in nine years. In 1997, tickets totalling £148,000 were issued, compared with 2006, when there were more than 17 times that, topping £2.5m. In the 12 months to August this year, 9,898 speeding offences were clocked by mobile cameras in the county.