Motorists are usually unaware - until police stop them

Mark Hutcheson, a 24-year-old student from Cardiff, said his car's plates were cloned around 2003. He believes those who copied them used the plates to carry out a string of robberies in South Wales.

"Whenever there were police cars lying on the side of the road, I used to get stopped," he says.

"It was really frustrating and a complete waste of time, because I would have to spend 15 minutes explaining myself each time."

He believes the plates had been flagged up on the DVLA website, but police never told him details.

He has not been pulled over for about two years, and believes the culprits were caught around that time. "If it wasn't the case I'd still be pulled over on a regular basis."

It seems strange - it makes you wonder if there's not something dodgy happening in their offices Paul Heath

Paul Heath, 39, a security operations manager from Letchworth Garden City, Herts, had a long-standing argument with his insurance company after they claimed his Vauxhall Vectra had been involved in a head-on collision with another vehicle last July.

"They pestered me quite a few times. They'd call me, leave it a few months, then ring back with the same questions. I said to them 'I don't know what you're talking about'."

Mr Hunt says the accident was supposed to have taken place in Manchester - a city he has never been to.

"They kept saying they would put a note on the computer. It seems strange - it makes you wonder if there's not something dodgy happening in their offices."

1950s incident

It is not a new problem, however - one reader told a story of a friend encountering the problem back in the 1950s. David Benson says his friend and their assistant saw a car the same colour on the Embankment in London, which they ended up following.

Thousands of plates are stolen every year

"It was then they realised the number plate was the same. They followed it through Victoria and on towards Chelsea. They spotted a policeman at a set of traffic lights, Sloane Square I think, and got him to stop the car in front.

"Turned out that the other car was the genuine plate and our friend had a cloned car. I don't know exactly where he bought it but he lived somewhere in the south London/Woolwich area and only had the car a couple of months.

"I remember him saying it would be the last time he pays a top price for a second-hand car at a 'reputable' dealer. Not sure of the outcome but think the dealer eventually gave him another car."