An investigation has been launched by the BEATT into the derailment of a TER train in Cléon on September 11. The incident injured 44 people and has raised concerns about railway safety. According to the first report released by the BEATT, the derailment occurred around 7:25 p.m. as the train approached crossing number 33. The train driver of train number 852 086 noticed a rail on one of the tracks of his line and immediately applied emergency brakes. The train was traveling at the speed limit of the line, 140 km/h, and hit the rail at a speed still close to that limit. The impact caused the train to partially derail, and a coupling failure occurred at the first carriage, between the leading motor car and the intermediate car. The report highlights that the BEATT will focus on several aspects of the incident. These include the sequence of events leading to the derailment, the presence of construction materials on the railway platform, the alerts and emergency measures taken, and how SNCF Réseau and SNCF Voyageurs handled the situation. The presence of construction materials on the tracks raises questions about safety protocols during railway maintenance. Investigators are examining whether these materials were properly secured or if there were lapses in communication or oversight. The report also notes the importance of understanding how the emergency braking system performed under the circumstances and whether it could have been more effective in preventing the derailment. The BEATT is also looking into the response from SNCF Réseau and SNCF Voyageurs, the two main branches of the French national rail company. Their roles include managing the infrastructure and providing passenger services, respectively. The investigation aims to determine if there were any procedural failures or if additional training or equipment could have helped prevent the accident or mitigate its effects. The findings of this investigation could lead to changes in railway safety practices across France.