At least six people died and a dozen were seriously injured when a train derailed and hit the platform at a station in central France on Friday, leaving several carriages torn and one lying on its side, officials said.
Local prefect Michel Fuzeau said nine of the 12 people injured were very seriously wounded, and Interior Minister Manuel Valls said the death toll would probably rise.
The train -- a regional service that travels more slowly than France's TGV express trains -- veered off the track en route from Paris to the city of Limoges at the station of Bretigny-sur-Orge, 16 miles south of Paris.
"The death toll is evolving constantly at this point and unfortunately it will probably rise," Valls said.
National rail operator SNCF said the train, travelling just as many French families were heading off on summer holidays, was carrying around 385 people and that an investigation was under way into what had happened.
"We do not know the cause of the derailment yet," SNCF Chairman Guillaume Pepy told reporters at the scene. The train was not scheduled to stop at Bretigny-sur-Orge but passengers told local media the train nonetheless appeared to be traveling unusually fast as it approached the station.
TV images showed one of the carriages smashed against a platform at Bretigny-sur-Orge station, 16 miles south of Paris. Trapped passengers were still being helped to safety.
"Most of the people who suffered minor injuries have been taken care of. We are going to have to empty the carriages completely to see if there are victims or not," said local lawmaker Michel Pouzol.