Authorities are investigating a train derailment in northwestern France that injured 44 people. The incident is suspected to be sabotage after a piece of rail was found on the track. The regional train, carrying 186 passengers from Rouen to Caen, derailed Friday evening in Cleon.

One carriage tipped onto its side, while four others left the tracks. An 18-year-old woman was among the injured and was evacuated by helicopter to Rouen University Hospital.

Investigators believe sabotage may have caused the derailment. The piece of rail found on the track is likely linked to the incident, according to a spokeswoman for the French national police communications service (SICOP). She spoke anonymously due to police policy.

Rouen prosecutor Sebastien Gallois indicated that the reasons for the rail’s presence are unknown and will be determined through investigation. Authorities are examining whether the circumstances were accidental or involved sabotage. The prosecutor’s office is cautious about drawing conclusions at this stage.

Cleon Mayor Melanie Delacour mentioned that victims are “in a state of shock.” The windows of the upright carriages shattered, and stones flew into the carriages due to the train’s speed.

France has experienced previous rail disasters. In July 2013, a derailment at Brétigny-sur-Orge killed seven people. In November 2015, a TGV train derailed during tests near Strasbourg, causing 11 fatalities.

More recently, a crash in southern Spain at Adamuz involved two high-speed trains and resulted in 46 deaths and over 100 injuries.