THIEVES who stripped 1,400m of valuable copper wire from pylons at Purleiu, near Lydney, are "dicing with death" says power distributor Central Networks.

The company has upped its reward for information leading to the conviction of anyone responsible for the attacks to £10,000.

Phil Wilson, Customer Operations Manager for Central Networks, said: "This is a new one to us – we've had people using chainsaws to cut through wooden poles and breaking into substations but climbing high into the sky to take cabling with 33,000 volts going through it is just plain daft.

"Even if you ignore the fact that they're putting their own lives at risk, they are also causing inconvenience to thousands of customers, costing us money and producing dangerous working conditions for our engineers.

"We're working closely with the police and Crimestoppers to ensure these criminals can be brought to justice, which is why we we've made the decision to increase the reward."

A police spokesman said: "People rely on a sound electricity network and that right is being jeopardised by these offenders. For the good of everyone in Gloucestershire, please call us if you have any information.

"I also want the public to know that progress is being made thanks to our partnership with Central Networks. Three people have been arrested and bailed in relation to the theft of 7km of cable from a farm in Fromebridge in September."

•The police in Monmouthshire are taking part in a Wales-wide alert to prevent metal thefts which in some instances are putting lives at risk. Thieves in recent times have taken culvert and manhole covers, road and rail signalling cables and other vital infrastructure items. Less serious but nevertheless distressing are thefts from buildings including lead roofing, and even public statues.

Gwent police want to hear of suspicious activities on 101, or people can ring Crimestoppers anonymously on 0800 555111.