Long-distance internet cables in France have been cut in an act of sabotage, causing disruption to internet services across the country. This is the second disruption during the Olympic Games in Paris, after high-speed train lines were targeted in a series of arson attacks hours before the Games kicked off.

Marina Ferrari, France’s junior minister for digital affairs, said on X that in the early hours of Monday morning, multiple locations around France were affected by several “damages” that impacted telecommunications providers and have resulted in “localized consequences” to fiber optic services as well mobile internet connectivity. Internet companies confirmed the damage.

The French Ministry of the Interior, which oversees policing agencies in the country, did not immediately respond to a request for comment. French cybersecurity agency ANSSI told WIRED the problems are not linked to a cybersecurity incident.

At the time of writing, nobody has claimed responsibility for either attack. Officials have yet to identify any suspects involved in the cable-cutting sabotage, but they believe the disruption to train services could have been committed by people with “ultra-left” political leanings.

The incidents around the Olympics come at a time when Russia has been blamed for a string of disinformation targeting France and has also been linked to a series of potential sabotage attacks in Europe.

The second largest French telecoms company, SFR, appeared to be one of the most impacted by the vandalism. “Our long-distance fiber network was sabotaged between 1 am and 3 am last night in five different locations,” a spokesperson from SFR told WIRED. SFR says its maintenance teams are working on repairing the damage and said the impact on its customers was “limited.”

“Also, between three and eight other operators are impacted since they use our long-distance network,” the spokesperson said.

Nicolas Guillaume, the CEO of telecom firm Nasca Group, which owns the ISP company Netalis, told WIRED he believed the damage was “deliberate” and that ISPs serving both customers and businesses have been impacted. Several of the damaged cables, according to images shared on X by the CEO, appear to have clean cuts across them. Guillaume says it is likely that people opened the ducts where cables are stored and cut them. Internet company Free 1337 also confirmed it was working on fixing the damage.

While billions of people around the world use wireless connections, the underlying internet backbone is made up of cables traversing across countries and under seas. This infrastructure, which is able to automatically reroute traffic to limit outages, can be fragile and vulnerable to attack or disruption. EU politicians have called for internet infrastructure security to be improved.

But the sabotage is not the first time that internet cables in France have been damaged in potentially deliberate acts. At the end of April 2022, crucial long-distance internet cables around Paris were deliberately cut and damaged—causing outages that impacted around 10 internet and infrastructure companies.

In that instance, according to photographs published by telecoms companies, the cables appeared to have been surgically cut, all at around the same time, in three locations, to the north, south, and east of Paris. Thousands of people around Paris—and also some farther away from the French capital—were plunged into a temporary internet blackout as network operators rerouted traffic. “It is the work of professionals,” Guillaume said at the time.

Arthur PB Laudrain, a postdoctoral research associate in cyber diplomacy at King’s College London, says the most recent incident seems “less serious” than the 2022 outages. “Such actions are within the capabilities of ultra-left or ecologist and anarchist groups, especially if they benefited from insider assistance or knowledge (current or former rail or network workers),” Laudrain says. “However, we cannot rule out the fact that a state actor is encouraging, supporting, or directing such domestic groups to create plausible deniability of their involvement.”