An effort to remove €10 million worth of copper wire from an ESB substation in Dublin was behind an explosion which caused 15,000 premises in the south and west of the county to lose power on Sunday night, a spokesman for ESB Networks has said.

The spokesman added that this was the largest attempted theft of copper wire from ESB installations to date.

The Inchicore facility, where the fire broke out, is one of the three major substations which handle the city’s entire power requirements.

Update:4 fire engs, foam tender +water tanker on scene. fast help from @ESBNetworks #fire #dublin pic Michael Shanks pic.twitter.com/kH9IIhLkDX — Dublin Fire Brigade (@DubFireBrigade) April 17, 2016

The company said it could have been a “serious event in terms of the national power transmission network”.

ESB Networks also said the repair bill would be a multiple of the cost of the wire because of the damage caused.

Over the last four years 150km of copper valued at €3 million has been stolen costing the company €28 million to replace.

ESB spokesman Conor Healy said over the last few weeks the company have endured several break-ins, including multiple break-ins on the same day.

Mr Healy said the attack on 220kV ESB substation at Jamestown Road, Inchicore, was the worst he had seen in almost 30 years.