French police used tear gas on Saturday as they clashed with protesters seeking to stop the construction of a new high-speed train line between France and neighbouring Italy which opponents argue will wreck the sensitive Alpine environment.
Some 4,000 protesters, according to organisers, and 3,000, according to police, turned out for the rally close to the village of Saint Remy-de-Maurienne in southeastern France in defiance of an official ban on the gathering, an AFP correspondent said.
Police then used tear gas when a faction of protesters began to hurl projectiles at security forces.
Protesters also stormed the nearby railway line, AFP reports, although train traffic had been halted due to the situation in the early afternoon, according to operator SNCF.
Backed by the European Union, the new line will link Lyon and Turin, with 70 per cent of the tracks in France and 30 per cent in Italy, and a 57.5 km tunnel crossing the Alps between Saint-Jean-de-Maurienne and Suse. The estimated cost of the project is more than €26 billion.
Supporters say it will greatly ease freight road traffic but opponents say the ecological damage risks being devastating and that springs are already starting to dry up due to the construction.