Police in Derbyshire say they've received two dozen reports of cooking oil theft in the county over the past three months.
They suggest that thieves are targeting businesses such as takeaways and pubs, in order to sell on the stolen oil to make biofuels for use in diesel vehicles.
The police also urged motorists to exercise caution when filling up their tanks, saying that the cost of living crisis could be encouraging drivers to use "seemingly cheap biofuels."
"However, in the long run use of such products is likely to cause increased costs as they can be harmful to modern diesel engines as they pose a serious risk of clogging fuel injectors and emission control devices," they said in a press release.
Police suggest business owners take the following steps:
Ask suppliers for locking barrels. Many cooking oil barrels have a securing ring around the top which can be padlocked to prevent siphoning
Ensure CCTV cameras and security lighting are installed to help deter thieves
Keep used oil barrels indoors if it is safe do so, or ensure they are out of reach of opportunistic thieves
Regular monitoring of used cooking oil levels will indicate if a theft has occurred. Alarms can also be installed in containers if it falls below a certain level