The number of catalytic converter thefts is ten times higher than what it was last year, police have revealed.

Figures obtained by the Observer showed 20 of the devices were stolen in Watford between August 8 and September 19 this year, but that number had only been two during the same time frame in 2018.

Hertfordshire Constabulary put the thefts down to thieves targeting the precious metals the catalytic converters contain, which include platinum, copper and nickel.

The force also confirmed that the devices, which cleans up harmful gases from a car engine before they exit the exhaust pipe, were most commonly stolen in Toyota Prius’.

More than half of the recorded catalytic converter thefts in the county involved the model, with Toyota Auris’ also being targeted.

Police warned drivers and businesses to be vigilant of the thefts, which has also been on the increase in Hemel Hempstead.

PCSO Daniel McManus, from the Hemel Hempstead Safer Neighbourhood Team, said: “Please remain cautious as thefts are happening both day and night – it is worth taking extra measures to ensure you won’t fall victim to this crime.”

Earlier this year the Steven Eagell Toyota garage in Ascot Road, Croxley Green, said it was struggling to deal with the number of people coming in for replacements of stolen catalytic converters.

A service worker at the garage told the Observer in September: “We physically cannot carry out the work.

“Toyota have not given us an estimated time of arrival as to when we can get parts to carry out the work.

“At the moment, we are struggling to deal with the amount of people coming for replacements.

“We have to explain to people that demand is quite high and people are unfortunately having to wait. It is a big problem.”

Toyota confirmed the increase in reported thefts has made it difficult to provide the needed parts and are taking “urgent” action to address the problem with suppliers.

A spokesperson said: “This sudden rise (of thefts) is one we could not have envisaged set against many years of low incidents of theft.

“This has impacted our ability to source enough of the parts we need in some cases, for which we sincerely apologise."