Investigators are examining a rail section found on the track, while prosecutors say no evidence yet proves a deliberate act.
CLÉON, France — French investigators are working to determine what caused a regional passenger train carrying 186 people to derail in Normandy, injuring 44, as authorities caution that the discovery of a piece of rail on the track does not yet establish that the crash was intentional.
The Sept. 11 derailment near Cléon, south of Rouen, has prompted separate judicial and technical investigations. A rail section found on the line remains central to the inquiry and may have contributed to the crash. However, Rouen prosecutor Sébastien Gallois has said investigators have not established that the object was deliberately placed there to derail the train. Interior Minister Laurent Nuñez also urged caution Sunday, saying investigators had neither ruled out nor favored a particular explanation.
The TER regional train was traveling between Rouen and Caen when it derailed at about 7:45 p.m. between the stations of Tourville and Elbeuf-Saint-Aubin. Authorities said 44 people were injured. An 18-year-old woman was initially considered critically injured and was flown by helicopter to Rouen University Hospital. Prosecutors later said fears for her life or a serious permanent disability had been lifted. No deaths were reported.
The derailment brought a large emergency response to the scene. Officials mobilized about 130 firefighters, five medical teams and 80 vehicles under a mass-casualty response plan. Passengers who did not require hospital treatment were taken to a building provided by local officials. By Sunday evening, prosecutors said only two victims remained hospitalized after another injured passenger was expected to be discharged.
Early attention focused heavily on possible sabotage after police said the piece of rail discovered on the track was probably connected to the derailment. That possibility generated public speculation about whether someone had intentionally interfered with the railway. Prosecutors later emphasized that the presence of the object and its role in the crash are separate questions from how it reached the track. Gallois said investigators had no evidence at that stage proving an intentional attempt to make the train derail, much less an attack.
Rouen judicial police are conducting the criminal investigation. Officers have interviewed witnesses and some passengers, completed additional forensic work and sought telephone and video surveillance records. A court-appointed expert has also examined the scene. Investigators are trying to reconstruct activity around the railway before the derailment, identify additional witnesses and determine the origin of the rail section. Prosecutors said passengers would be interviewed individually as the inquiry continued.
A second investigation is being conducted by France’s Bureau of Enquiries into Land Transport Accidents, known as the BEA-TT. The agency formally opened its investigation Sept. 12 and lists the Cléon derailment among its current cases. The technical inquiry is separate from the criminal investigation and is intended to establish the circumstances and probable causes of the derailment and develop safety recommendations. Gallois said the prosecutor’s office and the BEA-TT would coordinate and exchange necessary information while keeping their investigations distinct.
The crash left extensive damage along the railway. SNCF Réseau began preparing the area for removal of the derailed train by clearing vegetation and making the site accessible to heavy equipment. Two large Kirow rail cranes capable of lifting about 150 tons each were being brought to the scene Monday evening, with recovery planning scheduled to begin Tuesday. The lifting operation could take at least eight days before reconstruction of the damaged track can begin.
Rail service remains disrupted while recovery and repairs continue. Traffic is suspended between Rouen and Elbeuf in both directions, while trains are operating on portions of the route outside the damaged section. Buses and coaches are being used as alternatives for affected passengers. SNCF Réseau has not announced a date for reopening the damaged line because engineers must first assess the condition of the infrastructure after the wreckage is removed.
Authorities have not announced a finding that the derailment was deliberate, and no publicly identified suspect or motive has emerged from the verified investigation updates. Police examinations, witness interviews and the independent technical inquiry are continuing as crews prepare to remove the damaged train and determine the extent of repairs needed before full service can resume.
Author note: Last updated September 14, 2026.