Cyber attack shut down British power plant for four days

Why the cyber attack did not hit the grid

The site was disabled “while staff fought to bring it back online” after the July incident.

The exact location has been withheld for security reasons.

The plant involved was not one of the country’s biggest sites, according to the Telegraph, and the outage had no impact on the UK’s wider power supply or energy generation.

The Government has confirmed as much, describing the energy system as “highly resilient”.

The attack came at the same time as a series of strikes on water infrastructure in the United States, which affected 12 states and caused concern in the White House.

The disclosure, also covered by the Independent, follows a run of security scares in Britain that has already seen RAF jets scrambled over a suspected Russian bomber.

"We have thresholds for important generators to legally notify us of cyber activity, and this site is nowhere near," said a government spokesperson to the Telegraph.

"It’s a very small scale site, less than a rounding error compared to grid capacity."

The government spokesperson added: “The UK has a highly resilient energy system. We work closely with the energy sector to protect infrastructure and ensure the highest security standards.

"This story refers to an incident impacting a small-scale energy generator, and at no point was there a risk to the wider energy system.”

With rising tension between Russia and the West already unsettling European capitals, the question now is whether a bigger generator could be next, and how quickly the sector can harden itself against the next cyber attack.