First it was lead and copper that disappeared from roofs and railways. Now enterprising thieves are driving around the countryside in large tankers in the dead of night stealing domestic heating oil.

The modern burglar must keep one eye on the commodities markets to make a living. As the price of fuel has risen sharply, unscrupulous raiders have turned their attention to the oil tanks in back gardens.

Thieves have already taken advantage of the big increases in the price of lead, copper and other metals by stealing lead from the roofs of houses and churches. Door handles and manhole covers have gone missing and even statues have disappeared from town squares to be resold as scrap.

Now it is the turn of farmers and rural householders to become victims of market forces. What started

six months ago as a few isolated incidents has turned into a countrywide crimewave.

Police have reported an increase in oil theft, from Cornwall to the far north of Scotland, and are telling people to be on their guard and take extra precautions.

About 1.5million people use home heating oil in Britain. They generally live in rural areas and have no access to a gas main.

Six months ago domestic oil cost 37p a litre (£1.68 a gallon). Today it costs about 56p a litre. The average oil tank can cost £1,000 to fill.

Particularly at risk are properties in isolated locations, where crime has traditionally been low. In one three-week period this year detectives said that 36 oil thefts were reported in Suffolk alone.

In the past six months NFU Mutual Insurance has received more than a hundred claims from home and farm owners. The cost has exceeded £50,000. Some thieves are brazenly driving tankers into farms; others are using large vans with tanks in the back. In one go, they are stealing up to 800 litres (176 gallons) of fuel, worth more than £500.

Tim Price, from NFU Mutual, said: “It's a new crime as far as we are concerned; we had not seen domestic oil being taken until about six months ago. Thieves will steal anything that they realise is valuable; we have seen it with scrap iron. They see where the money is and then follow it.

“We didn't come across these thefts until last year but in the past six months there has been quite a rash of heating oil thefts going on across the country.

“We estimate that there have been over 100 claims in that time and we are looking at a cost of over £50,000. [Oil] is a lot more valuable than it used to be and much more appealing to thieves despite it being difficult to remove from premises.”

The company is alerting customers to the threat and advising them to secure their premises with gates, fences and padlocks. They are even suggesting that tanks visible from

the road should be relocated or camouflaged.

Mr Price added: “The valves can be padlocked but they can be cut or pulled off, which can lead to other problems. The oil can leak into the ground and cause pollution or the tank has to be replaced, which costs more than replacing the oil.”

He said that domestic tanks could hold up to 800 litres, which will last for about two months. One claimant had his tank emptied completely two weeks after it was filled.

A spokeswoman for Devon and Cornwall police said: “Owners of tanks are urged to check tanks and review security by locking tanks if possible.”

Ian Johnson, the South West National Farmers' Union spokesman, said that he was not surprised at the thefts, given the price of the oil. “We must always be vigilant about the possibility of theft - the last thing farmers want is to have their fuel pinched,” he said.

Down a narrow country lane in the Scottish Highlands, Mark Thomson was still trying to make sense of the highly unusual crime scene outside his back door yesterday.

Days ago he and his wife became the victims of a fuel theft carried out in the dead of night as they and their daughter slept.

Mr Thomson, 40, said: “The police were here checking for fingerprints but they haven't said if they think it'll get solved or if they know who did it. It's a bit of a mystery.”

The thieves pulled up alongside the 1,200-litre (264-gallon) fuel tank in the driveway of the Thomsons' farmhouse, five miles outside the Perthshire town of Crieff, unscrewed the lid and siphoned off 700 litres of heating oil worth several hundred pounds. Then they put the lid back on and drove off.

In the Crieff area a spate of incidents in the past three weeks has shattered the rural calm. At least three robberies have been carried out on domestic heating tanks, worth a total of about £700.

In Crieff, there have also been reports that at least one gang has armed itself with a crossbow to defend itself during the raids.

Vivian Donaldson, 60, who lives near the Thomsons, said: “We've never heard of this sort of thing before and can only assume it is linked to the rising fuel prices.”

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