Rise in catalytic converter thefts in Oxfordshire
Thefts of catalytic converters from cars in Oxfordshire have risen from zero last year to 24 so far in 2010.
Catalytic converters use precious metals platinum, palladium and rhodium to remove toxins.
An increase in thefts across the UK is blamed on soaring metal prices, with a single device fetching up to £70 on the black market.
Pc Phil Marstin said: "There are a lot of valuable metals inside the catalytic converter which are then sold on."
The theft can take place within 45 seconds and replacement costs can be up to £1,000, he added.
Larger 4x4 cars or trucks tend to be most at risk since the catalytic converter is more easily accessed.