Police have increased patrols in South Lakeland to combat a massive rise in metal theft, after metal, particularly copper, was stolen from roofs, tradesmen's vans and outbuildings.

Police have increased patrols in South Lakeland to combat a massive rise in scrap and metal thefts. The move follows an increasing trend in thefts of metal – particularly copper – from tradesmen's vans, roofs and outbuildings.

Cumbria Police have been notified of 94 metal thefts in the south of the county since January, with stolen metals valued at £85,000. Last week, officers targeted suspicious vehicles and visited scrap yards and builders' merchants seeking intelligence.

"The price of metals is very high at the minute so it makes it quite a lucrative item to steal," Sergeant Bill Nolan, of Kendal Police, told the West Morland Gazette.

"Stealing scrap metal is flavour of the month at the moment, so tradesmen should be warned not to leave metal, tiles and power tools lying around, and keep them out of sight. Once taken it is very difficult to catch because this is happening over such a large area."

Shane Blezard, from Kendal Scrap Metals, Mintsfeet, said the problem was likely to get worse before it got better. "Scrap metal prices are at an all-time high and they've been like that for about a year," he said. "The people doing this seem to be opportunists who see what's going on around them, and then they just pinch any scrap metals."

Last week thieves entered a warehouse in Bentham and stole boxes of brass valves and fittings worth £5,000.