Police across the country are responding to greater numbers of the thefts, in which thieves force open fuel caps to siphon off fuel.
Nottinghamshire is emerging as a trouble hot spot, and police in the county have put additional patrols in place to combat the problem. Inspector Mark Webster, who oversees community policing for areas within Mansfield North, said: "With the credit crunch we have seen fuel prices increase significantly. Unfortunately, we find thieves will also look to take advantage by using other people's fuel for their own measures, often to commit other crime, or they will sell it on."
Webster said retailers could better protect themselves by taking a variety of steps, including parking their vans with the fuel-cap close to a wall, improving lighting and CCTV in parking areas, purchasing a locking fuel cap, and using alarms.
He added: "We need people to be vigilant when parking their vehicles. We want them to be forewarned that this is happening and to report anyone acting suspiciously to the police."