Vandals are being blamed for a power cut which blacked out 10,000 homes and business on the border of Sheffield and Rotherham on Wednesday evening. Electricity firm YEDL switched off supplies while a fire was put out at the base of a 132,000 volt pylon at Blackburn Meadows.
Engineers restored power supplies to all the properties within 30 minutes.
Geoff Earl, from YEDL, said if a power line had been brought down someone could have been injured or killed.
"This act of mindless vandalism is extremely dangerous as well as being a major inconvenience to our customers," Mr Earl added.