'As long as Britain's government pursues pro-Ukraine policies, we will attack them'

In messages exchanged with The Observer, a pro-Russian hacking group pledges to disrupt UK businesses and infrastructure.

- Alexi Mostrous reports

"Englishwomen," the hacker said, "always play dirty.

The head of Z-Pentest, a pro-Russia hacking group, was speaking idiomatically, using an anti-British proverb from the 19th century.

But in an interview, his message was clear: Britain was a target. “As long as the British government continues to foster anti-Russian sentiment and pursue pro-Ukrainian policies, we will continue to attack them,” the hacker said in a series of messages exchanged with The Observer last week.

Z-Pentest is one of a new wave of “patriotic” hacking groups connected to Russia and China whose aim is to destabilise the west. Unlike many hackers who limited themselves to disabling “enemy” websites, Z-Pentest and others are increasingly targeting critical infrastructure.

The group, which formed last year, claims to have hacked into a hospital in Poland, a commercial ventilation system in Romania, an unnamed sterilisation unit in the UK and a food storage system in Ukraine. In May it posted a video showing its hackers in Poland apparently raising temperatures at the warehouses of the supermarket Lidl to “a scorching desert”.

The Observer has seen videos purporting to show these attacks but has not verified them independently. A spokesperson for Lidl said all its warehouses in Poland were operating normally but that it treats reports of hacking with “utmost seriousness”.

“Hacktivists are increasingly targeting critical infrastructure,” Kaustubh Medhe, vice-president of research at monitoring organisation Cyble, said. “Critical infrastructure needs to be better secured.”

Last week the National Cyber Security Centre (NCSC) warned that such groups were a rising threat: “Russia’s invasion of Ukraine and the ongoing Israel-Gaza conflict have inspired a growing number of pro-Russia hacktivist groups seeking to target the UK, Europe, US and other Nato countries. They choose their targets based on what is vulnerable.”