Criminal gangs are pocketing hundreds of thousands of pounds by stealing metal from homes and churches, then selling it on at scrapyards for sky-high prices.

Police believe the rising price of metal around the world has now made theft so profitable that criminal gangs are being attracted away from other crimes.

In the past year, the price of scrap metal has increased four-fold - with 1,877 metal thefts reported in Oxfordshire over the same period.

Organised gangs are targeting lead from roofs, stripping copper from houses, scrapping stolen cars and even stealing playground slides and litter bins.

Opportunist thieves are simply turning up at scrapyards with stolen metal in shopping trolleys or wheelbarrows and walking away with a pocketful of cash.

Pc Jim McGuinness, who has collected information on metal thefts over the past year, said gangs of low-level criminals have been attracted by the promise of massive profits.

He added: "More and more criminals have been getting involved.

"We've always had people trading in scrap metal, but now we're seeing all types of the criminal fraternity.

"Some people see it quite simply as a way of making easy money and are jumping on the bandwagon."

Already this year, there have been 141 metal thefts in the county.

The price of a tonne of lead has risen from £150 to almost £1,000 over the past 12 months, while a tonne of copper, which was less than £2,000 a year ago, can net a criminal up to £5,000.

Demand for metals in China and the Far East has boosted the price of scrap.

Oxfordshire commander Chief Supt Shaun Morley said: "This crime has increased because of the increase in price of metals.

"This has happened in a short space of time and we are working with scrap dealers and local authorities to tackle this crime."

But Tony Bradford, of Metal Salvage, in Jackdaw Lane, Oxford, said it was almost impossible to know if the metal was stolen and called for more police support.

He added: "We've had people come in with shopping trolleys and a reel of copper.

"Others have turned up on their bikes with lead flashings or metal piping under their arms or with a wheelbarrow of the stuff.

"It is true that people are stealing metal. In my 40 years in the business, I've never known the price of scrap metal to be so high.

"But apart from doing the right thing and taking down the name, address and car registration, there is not much more we can do. If someone turns up with a shopping trolley, all we can do is check their identification."

Frederick Smith, of Frederick Smith Scrap Metal, in Bicester, said: "There is no doubt that people are stealing it.

"If you went back two years, we were paying you to clear away scrap metal. The prices are off the scale and still rising."

As well as targeting churches, schools, homes and businesses, criminal gangs have stolen old cars, playground slides and memorial plaques.

Lead has been stolen from dozens of churches, including St Mary's Church in Garsington and St Nicholas Church in Tackley, where thieves attacked a church warden.

Some schools have been left with leaky roofs after thieves climbed on their roofs and stripped enough lead to earn them thousands of pounds.

Businesses stocking large amounts of metals have also suffered break-ins, including burglaries at building merchant Travis Perkins in Chipping Norton, where £9,000 worth of lead and copper tubes were stolen.

About £55,000 worth of metal marquee poles were stolen from Thame Showground.

Copper pipes and water boilers have been stripped from empty or renovated homes and police in South Oxfordshire and Cherwell have seen an increase in thefts of cars to be sold for cash at a scrapyard.

Metal litter bins worth £550 each have been stolen in East Oxford and slides from playgrounds in Blackbird Leys have gone missing.

About 200 bronze plaques were stolen from the crematorium in Bayswater Road, Headington, last September.

In January, thieves stole a classic Daimler Sovereign car from Ashhurst Way in Rose Hill belonging to Robert Penny, who had recently died, then sold it for scrap.