Hackers backed by the Russian government have attacked energy networks running the national grid in parts of the UK, The Times has learnt.

The hackers, who targeted the Republic of Ireland’s energy sector, intended to infiltrate control systems, security analysts believe. This would also have given them the power to knock out parts of the grid in Northern Ireland.

Senior engineers at Ireland’s Electricity Supply Board (ESB) were targeted last month by a group understood to have ties to the Kremlin’s GRU intelligence agency. The hackers sent emails designed to trick staff by drawing on extensive surveillance of ESB practices and contained malicious software.

There is no evidence of disruption to the network, but security analysts monitoring Russia’s cyberintelligence groups said that the hackers probably