Police are appealing for information and witnesses following reports of earthing cable theft in the Maesycwmmer, Hengoed, Llanbradach and Ystrad Mynach areas.
The incidents have been reported over the last three weeks.
Residents have also raised concerns about a green vehicle with Irish registration plates which has been seen in the area.
If you have any information relating to this vehicle or these incidents, please call 101 or Crimestoppers on 0800 555 111.