France’s high-speed train network was on Friday targeted by “coordinated acts of sabotage” ahead of the opening ceremony of the 2024 Olympics in Paris, the country’s Prime Minister Gabriel Attal said.

The prime minister said the consequences of these acts of sabotage were massive and serious. “Our intelligence services and law enforcement have been mobilised to find and punish those who carried out these criminal acts,” he said in a social media post.

France’s Transport Minister Patrice Vergriete said that attacks at three places involved cable clusters connected to the train network being set on fire, CBS News reported. He added that everything indicated that these were “criminal fires”.

The 2024 summer Olympic in Paris are set to begin on Friday in the country and will end on August 11. Some of the competitions in the international multi-sport event began on Wednesday.

The country’s state railway company SNCF said on Friday that several trains were diverted or cancelled “due to coordinated acts of malice” that disrupted several high-speed lines.

“Our teams are fully mobilised in stations, in the call centers, and onboard to ensure that all passengers are informed and can reach their destination,” the state-owned company said.

The SNCF claimed that the areas affecting the railway track intersections were targeted to “double the impact”, the Associated Press reported. “For one fire, two destinations were hit,” the state-owned enterprise’s CEO, Jean-Pierre Farandou, said.

The Paris prosecutor’s office has begun an investigation into the attacks and has filed four separate charges in connection with damage to state property and taking part in organised crime, CNN reported.