Thousands of people have been left without power after a huge increase in theft of copper from electricity poles, including the Wolverhampton area.
Energy giant E.ON said thieves have gone to extreme lengths to steal copper, using chainsaws to cut down poles and leaving live wires dangling loose.
A total of 14 poles were cut down in the Central England region last week, including one at Wednesfield, near Wolverhampton, cutting power to 4,600 customers, and two in Doddington, Lincolnshire, which left almost 2,000 people without power.
In some case, live wires were left hanging just a few feet from the ground.
John Crackett, managing director of E.ON's distribution business, said: "Like everyone else, we've seen metal thefts increasing for a number of years, but what we hadn't seen before were thieves going to such lengths.
"They use a chainsaw to cut down the wooden poles and get access to our cabling.
"Even ignoring the danger of cutting down a pole that has wires carrying 11,000 volts at the top of it and leaving those wires - which could still be live - hanging near to the ground, this costs us money and causes massive inconvenience to our customers."