A Tauranga power substation has been forced into an emergency shutdown after thieves broke in and stole copper earthing equipment.
Powerco are today making urgent repairs at the Waihi Rd facility after the theft, which happened sometime on Monday night or Tuesday.
The company is offering a reward of up to $10,000 for information leading to the arrest of the copper thief.
Powerco network operations manager Phil Marsh said the theft had placed lives at risk.
"These thieves have placed the safety of the network at risk to make few hundred dollars from scrap copper.
"Electricity networks require effective earthing to operate safely and reliably and these selfish idiots have put the network and potentially customers at risk,'' he said.
Powerco is New Zealand's second largest electricity and gas distribution utility with around 400,000 consumers connected to its networks.
Mr Marsh said the company had been able to avoid cutting power to any customers by switching the load to other sub-stations.
The Waihi Rd facility was temporarily shutdown for urgent repairs.
Mr Marsh said the company would pay a reward equivalent to any reparation order up to a maximum of $10,000 for information that led to the arrest, conviction and a subsequent reparation order for the theft.
Anyone with information about the theft has been asked to contact Tauranga police on 577 4300 or Powerco on 0800 769 372.