Fires started in railway cabling have impacted up to 800,000 people across the French railway network on the eve of the Paris Olympics.
"Train operator SNCF's chief executive, Jean-Pierre Farandou, said the attackers had started fires in "conduits carrying multiple (fibre-optic) cables" that carried "safety information for drivers" or control the motors for points."
Seems this attack is becoming more common place. Used to just be the occasional tractor or digger damaging fibre but now it's seems to be intentional.