A rail fragment on the Rouen-Caen line puts sabotage at the centre of a 44-injury derailment

A TER service from Rouen to Caen derailed at Cléon, in Seine-Maritime, at about 19:45 on 11 September. One carriage overturned. Four others left the rails. Of 186 passengers, 44 were injured. An 18-year-old woman was flown to Rouen University Hospital in critical condition. Prosecutor Sébastien Gallois said on Saturday that her life was no longer in danger. The other injured have been treated and most have been discharged.

Gallois stated the leading theory in one sentence: a piece of rail was present on one of the tracks and may have caused the derailment. Why it was there is unknown. The train's recording device has been seized. A court-appointed expert is on the file. Several interviews are scheduled. The driver tested negative for drugs and alcohol. Police sources told French outlets the train was doing about 140 km/h when it hit a metal object. Social media users posted photographs of a rail section lying by the line. Investigators have not confirmed that those pictures show the object in question.

A spokeswoman for the national police communications service, SICOP, speaking without attribution under standing rules, told the Associated Press the rail fragment was "probably" linked to the derailment. The Rouen prosecutor's office has opened an inquiry into the causes of serious injuries and assigned it to the Rouen judicial police. Officials have used the words "malicious act" and "sabotage" in briefings while still refusing to close the accident file.

Cléon sits just south of Rouen, near Renault's factory. Authorities activated a mass-casualty plan. About 140 firefighters, five medical teams and 80 vehicles went to the site. SNCF shut the Rouen-Caen line and the Caen-Le Havre line and put buses on the road. The Rouen-Caen track reopened on 12 September. A passenger named Louis told ICI Normandie radio that the train gave a few jolts and then, after about three seconds, the motion grew violent.

French main lines have seen cable theft, vandalism and, in past protest waves, organised interference. A cut rail section placed on a running line is a different class of act. It implies tools, time on the track and knowledge of the timetable. If the expert confirms that the fragment was not a broken rail from the same line but a placed object, the charge sheet moves from accident to a criminal attempt against a passenger train.

The 18-year-old's condition is the human measure of the night. The operational measure is that a busy Normandy corridor was closed for hours and then reopened under investigation. The political measure will arrive only if the inquiry names a motive. Until then the facts are physical: 186 people on a TER, 44 hurt, a rail fragment on the ballast, a driver who was sober, and a prosecutor who has put sabotage at the front of the file without yet calling it proved.