The French interior minister said today that he cannot rule out the involvement of a foreign country in the acts of sabotage committed against the high-speed rail network (TGV) causing problems for the movement of travelers on yesterday’s opening day Olympic Games.

The attacks in the early hours of Friday destroyed infrastructure along railway lines linking Paris to cities such as Lille in the north, Bordeaux in the west and Strasbourg in the east.

Another attack on the line Paris-Marseille was prevented, French railway company SNCF announced.

There was no immediate claim of responsibility.

“Who is responsible? Whether it comes from inside the country or there was an order from abroad, it is too early to say. We have identified a number of elements that lead us to the conclusion that we will find the culprit soon enough,” said Gerald Darmanen on the France 2 network.

On Friday, two security sources said the modus operandi of the saboteurs initially drew suspicion to far-left organizations or environmental activists, but that there was still no evidence.

Traffic on the TGV network will be restored on Monday, Transport Minister Patrice Vergriet and SNCF chief Jean-Pierre Faradou told reporters yesterday.

SNCF reiterated that plans to transport competing teams to the Olympics are guaranteed.

Yesterday, 100,000 people were unable to travel by train and another 150,000 experienced delays in their journeys but eventually reached their destination.