The number of catalytic converter thefts across Hertfordshire has surged during the coronavirus lockdown, police have said.

Hertfordshire Constabulary says thefts of the devices more than doubled across the county, with 116 offences having been recorded between April 1 and June 30 this year compared to 45 in the same time period in 2019.

St Albans has seen the largest increase in the county with 28 offences - up from five in 2019 - and Hertsmere had 23 offences compared to eight last year.

Catalytic converters, which contain precious metals such as platinum, copper and nickel, cleans up harmful gases from the car engine before they exit the exhaust pipe.

And it seems that thieves are targeting the devices on hybrids models of Toyota and Honda brands, according to police.

Inspector Nicola Dean, from the Constabulary’s Crime Reduction Unit, said: “Whilst most crime has reduced during lockdown, criminals have been targeting vehicles for their catalytic converters, which they sell for the precious metals used to build the units.

"The criminals have been especially targeting hybrid models of Toyota and Honda brands so I would advise owners these types of vehicles to get their catalytic converters security marked and invest in a catloc device to deter thieves."

The county's police force also warned keyless thefts of vehicles has also been on the rise during the lockdown, with thieves using a device to bypass a vehicle’s security system by using the signal from a key fob to unlock and start the engine.

There have also been several reports of a scam targeting vehicles being sold privately, where criminals arrive to view the vehicle and switch the key fobs with a replica.

They then return at a later time and steal the vehicle using the stolen fob.

Inspector Dean added: “We have also had an increase in the theft of keyless entry vehicles, with thieves using electronic devices to boost the signal from the vehicle’s keyless fob. If the key is close enough to the vehicle, even if it is inside the home, the device can detect the fob signal and use it to open and start it.

"There’s a number of steps you can take to prevent this but one of the most effective deterrents is an old fashioned steering wheel lock.”

Drivers are being urged to keep their vehicles safe this summer and police have issued the following advice.

To help protect your catalytic converter:

• Don’t park your car/van half on the pavement as it makes it easier for the thieves to get underneath it.

• If you have a diesel van or other high clearance vehicles having your catalytic converter marked, or secured can deter thieves who steal them for the precious metal components.

• Park in a garage or other secure area if possible.

• Consider property marking your catalytic converter. It is cheap and may reduce your insurance.

• A sign in your window saying your catalytic converter has been marked may well deter thieves.

• Consider buying a catloc clamp to secure your catalytic converter to your vehicle and get it security marked.

To help prevent your vehicle being stolen:

• Never hand vehicle keys over to a third party or leave the vehicle unattended at a valet parking, car wash or other parking places, where criminals can gain access to the vehicle and code a key electronically.

• Consider fitting an ‘OBD safe’, a secure lockable device that fits over the vehicle’s on board diagnostic (OBD) port, in the vehicle cabin. This prevents criminals using software to code a key from the vehicle.

• Consider fitting a dual band tracking device that works on VHF/UHF and GPS, to make it more difficult for the tracking signal being blocked.

• Criminals can also employ remote/keyless entry jamming equipment so make sure your car is locked by trying the door before leaving it.

• Ensure that ‘home’ on your vehicle ‘Sat Nav’ is shown as the post code of your local police station and not your actual home address.

• Use an approved steering wheel lock and never leave your vehicle unlocked – even for a moment