A spokesperson for Duke Energy says the energy provider is "taking measures to strengthen security" at its power substations in the Carolinas following another outage caused by a suspected copper thief.

Investigators say a man was electrocuted after breaking in to Duke's substation on Battleground Highway in Cowpens Monday night. Fire officials believe the man was trying to steal copper from the equipment in the substation when he sparked a fire, causing about 3,000 people to lose power.

It's at least the fourth time since October 2010 that a suspected copper thief has caused an outage. In at least one other instance, the suspected thief was electrocuted. Duke spokesperson Betsy Conway says the company is taking measures to increase security at substations "as we speak".

"We are currently working on increasing all aspects of our security measures including our fencing," says Conway. "For obvious reasons, we don't want the thieves to know what we're working on," says Conway. "But changes are coming, including some you may not see."