Police are urging workmen to be more careful in locking up their vans after a spate of tool thefts from vans in the last few weeks.
Chief Inspector Stuart Greenfield, local police area commander for Chiltern said: "We have seen a real increase in the theft of tools from work vans in our area, particularly Chalfont St Giles, Chalfont St Peter and Chesham.
"It usually when they are parked outside somebody's house and there has been a really significant spike in the last couple of weeks.
"The message is, make sure your vans are locked up. If you are working you might shut the rear door to the van but you need to lock it as well because it is an opportunistic crime.
"Also if anyone sees anyone hanging around vans who are not the owners or workmen, let us know."
If you have any information call Thames Valley Police on 0845 8 505 505.