One in four rush-hour drivers are illegally nipping in and out of a park-and-ride to beat traffic queues.

An investigation by the Oxford Mail revealed the true level of cheating motorists who abuse the park-and-ride system to shave time off their journey and get past law-abiding commuters waiting in queues.

We spotted 76 out of 280 motorists in just one hour - more than one a minute - driving along the lane for buses and park-and-ride traffic, turning left into the Seacourt Park-and-Ride and either doing a U-turn immediately or driving around the roundabout and back out into the traffic in Botley Road.

Police and council officers said doing this was an offence which carries a £30 fine, but admitted it was a difficult problem to enforce.

However, drivers will be forced to mend their ways or pay up when a special bus lane camera is installed near the Park-and-Ride.

David Robertson, Oxfordshire County Council cabinet member for transport, said: "I understand the frustrations of drivers who stick by the traffic signals and stay in their lane.

"They then find people have come down the bus lane, sometimes turning into the park-and-ride, before they cut into the proper traffic.

"The police have carried out enforcement. One of the things we have been waiting for is the right legislation for a camera, which is the best way to enforce this.

"It is not going to be long before we have a camera in place."

Cameras would first be placed in Castle Street, High Street and Magdalen Street, to stop drivers who try to cheat daytime traffic restrictions in the city centre first.

He added: "After that we will review what will be needed in terms of cameras on bus lanes. The bus lane on Botley Road is by far the worst in terms of people abusing it."

He admitted that it would be difficult because it would be unfair to fine a stranger to Oxford, who turned on to Botley Road into the bus lane and realised they had gone wrong and rejoined the normal traffic lane.

Chris Hulme, Thames Valley Police traffic management officer, welcomed the camera proposal, but feared it would be difficult to prove if cars drove into the park-and-ride and out again.

He said: "I wouldn't have thought one camera would suffice.

It will need to confirm that people are using the bus lane, going into the park and ride and coming back out again.

"If they provided that sort of facility it would catch all the offenders, but you would have to prove they were going in and out of the road to the park-and-ride.

"It is very difficult to catch everyone because there are so many people doing it and it is difficult for police to enforce this on a constant basis. To provide photographic evidence is the way forward."