France's national rail operator SNCF says repairs to its infrastructure have been completed following a suspected coordinated arson attack on Friday, just hours before the opening ceremony of the Paris Olympic Games.

Staff worked all hours to manually restore and replace damaged fiber optic cables, which were targeted on rail lines in the north and southwest of the country, and in Brittany, on the north-western coast, while an attempt to destroy safety equipment in another region was foiled.

It is estimated that around 250,000 passengers were affected in the immediate aftermath of the attacks, with as many as 800,000 people impacted over the weekend, including one in four services on the Eurostar service between London and Paris being out of action, but services were largely back to normal on Monday morning.

"Thanks to the exceptional efforts of SNCF Network staff, who worked non-stop since Friday morning, repairs are now fully completed on all the high-speed rail services affected by the sabotage attacks," said a statement from the rail operator.

"Tests have been conclusive and the train lines are now able to function as normal. There will be no more disruption from Monday morning onwards."

Security around the Games has been at the highest level possible, and Interior Minister Gerald Darmanin told the France 2 television network that whoever had launched the attacks had failed in their main intention, as the opening ceremony was unaffected and the early stages of the Games have progressed smoothly.

"We have uncovered a certain number of elements that allow us to think that we will soon know who is responsible for what clearly did not sabotage the Olympic Games, but did sabotage part of the holidays of the French people," he said.

No group has yet claimed responsibility for the attacks, but several media outlets received messages afterwards expressing support for the attacks and criticizing the Olympic Games as a "celebration of nationalism".

In another later interview with the same television channel, Darmanin said investigators were "leaning towards the likelihood "that far-left extremists had carried out the attacks, and possible suspects had been identified.

"This is the traditional type of action of the ultra-left," he said, but added that "we must be cautious "in making assumptions, as a major question was "to know whether they were manipulated" or acted "for their own benefit", suggesting that they may have been encouraged by others.

On Monday morning, France's Junior Minister for Digital Matters Marina Ferrari issued a statement on the social media platform X saying the country's telecoms network had suffered isolated outages after overnight acts of vandalism, which would affect some fixed and mobile services.

The Olympic Games, which are followed by the Paralympic Games, are taking place at venues across the country, but mainly focused around Paris, and run until Aug 11.