Police officers are “stealing” valuables from cars in a bid to teach motorists a lesson if they leave them unlocked.

Owners who fail to lock their doors may return to find belongings – anything from wallets to sat-navs – have been taken and replaced with a letter saying: “A theft from your motor vehicle has been prevented.”

Richmond police introduced the drastic measure, where officers safeguard the items until they are claimed by the owner, in a bid to halt a rapid rise in thefts.

Since April there have been more than 300 reports of items being stolen from parked vehicles – up 40 per cent on last year’s figures – and 21 per cent of these involved thefts from vehicles left insecure.

After repeated requests for information about the initiative, the Richmond and Twickenham Times was sent copies of the three different letters officers can leave in cars but Richmond police refused to comment further, other than to say the tactic had not yet been put into practice.

However, Richmond Council’s cabinet member for communities, Councillor David Williams, was quick to throw his support behind the scheme – and believed officers had already tested out their new powers on unsuspecting drivers.

He said: “People can be really thoughtless.

“What the police are doing is only putting notices inside cars and taking valuables into safe keeping if the car is unlocked.

“They are leaving a notice inside the car saying something along the lines of ‘you will be pleased to know that your valuables are in police custody and not in the hands of a criminal’.”

Coun Williams added the reaction from most of the people who had received the notices was “absolutely relieved and grateful”.

He added: “They will tell their friends, if they are not too embarrassed.”

Coun Williams described it as a trial initiative, which had been running for a matter of weeks.

Have you received one of the letters? Do you think the scheme is a good idea? Tell us using the comment box below.