REPORT: Russia hacked UK energy companies on election day

Russian President Vladimir Putin and Industry and Trade Minister Denis Manturov watch a display during the MAKS 2017 air show in Zhukovsky, outside Moscow, Russia, July 18, 2017.

LONDON — UK energy companies and other "critical infrastructure" were targeted by hackers believed to have been backed by Russia during last month's general election, according to Motherboard and The Telegraph.

GCHQ's National Cyber Security Centre recently sent a letter to UK energy companies, manufacturers, and water companies that was leaked to Motherboard, Vice's technology website.

The letter warns that the spy agency detected "advanced state-sponsored hostile threat actors, who are known to target the energy and manufacturing sectors," according to Motherboard. The attack began on June 8, the day of the snap election.

The letter does not name the state thought to be behind the attack but the Telegraph reported on Wednesday that it believes Russia to be the country behind the attack.

While there no disruption was caused, the GCHQ letter warns that "a number of Industrial Control System engineering and services organisations are likely to have been compromised." Motherboard said the nature of the attack suggests that hackers may have been trying to harvest usernames and passwords from the target companies.

In a statement released to Motherboard, the NCSC said: "We are aware of reports of malicious cyber activity targeting the energy sector around the globe. We are liaising with our counterparts to better understand the threat and continue to manage any risks to the UK."

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