Thefts of catalytic converters from cars increased by half in London between 2019 and 2020, new figures have shown.

Catalytic converters reduce toxic pollution by controlling the emissions from a car’s exhaust, but they are often targeted by thieves for their valuable metal content.

There were 14,684 recorded incidents of catalytic converter thefts in the capital during 2020, compared to 9,576 the previous year.

Of the 32 London boroughs, 27 saw increases in the number of recorded incidents last year with Barnet seeing the highest number of thefts at 1,114.

Other boroughs with notably high numbers of thefts were Croydon at 951, Enfield at 883 and Harrow at 687.

The figures were obtained by the London Liberal Democrats following a question to the Mayor of London at a London Assembly meeting last month.

Lib Dem Assembly member Caroline Pidgeon said: “These are startling figures. A crime that hardly existed in 2017 is now prevalent in every part of London, leading to serious financial loss for thousands of people and a rise in car premiums for everyone.

“Although there is some useful crime prevention advice for motorists the big picture is that not enough measures are being taken to tackle the gangs behind this crime. The number of people who have been arrested for these offences in the last four years is pitifully low.

“When I questioned the Mayor of London on the rise recently, his response was to say that he had written to the Society of Motor Manufacturers back in 2019. Since then these offences have soared to even higher levels. Real and comprehensive action to tackle this soaring crime is long overdue and desperately needed.”

Despite the increase in recorded incidents, only 42 arrests have been made in relation to catalytic converter thefts since 2017.

The number of recorded thefts has increased every year since 2017 when there were only 173 recorded incidents.

In response to Caroline Pidgeon’s question last month, Mayor of London Sadiq Khan said that the Metropolitan Police were working with national forces “to develop and improve intelligence flows on theft and supply chains, proactively target criminals and improve prevention techniques”.

Both the Metropolitan Police and The AA advise that the best way to prevent catalytic converter theft is to park vehicles in a secure car park or garage. If that is not possible, they advise to park in a well-lit busy area.

Taller vehicles such as 4x4s are at greater risk of catalytic converter theft as they sit higher off the ground, allowing easier access for thieves.