Arsonists targeted France's high-speed TGV network in a chain of coordinated attacks, causing major disruption along the country's busiest railway routes before the Paris Olympics opening ceremony on Friday. 

"Last night, the SNCF was victim of several acts of vandalism on the Atlantic, Northern, and Eastern high-speed lines. Fires were deliberately set to damage our installations," the SNCF, France's state-owned railway company, said in a statement.

800,000 passengers have been affected by the sabotage, the president of the SNCF group told French news broadcaster BFMTV, adding the network is aiming to mobilize hundreds of personnel to repair the railways as soon as possible. 

Crucial train routes that connected multiple cities to Paris were targeted, including Lille in the north, Bordeaux in the west, and Strasbourg in the east.

The railway operator urged travelers to postpone their trips with trains returning to their original departure locations as repairs are underway. 

France tightens security ahead of Paris Olympics

Following the attacks, the Paris police chief said he would be increasing security across the capital, especially at Paris' main railway stations.

France has deployed significant numbers of security personnel to safeguard the Paris Olympics over the next month, including 45,000 police, 10,000 soldiers, and 2,000 security agents. In addition, snipers will be positioned on rooftops with drones providing aerial surveillance during the games.

French officials condemn the attacks

Responsibility for the attacks was immediately claimed, but it has not been determined whether the sabotage was politically motivated. 

Patrice Vergriete, France's Minister of Transport, described the attacks as criminal.

"It's completely appalling," Sports Minister Amelie Oudea-Castera told BFMTV, adding, "To target the games is to target France."