Spanish investigators are examining whether a failed automatic safety system and a controller’s decision to let trains move again led to the Oct. 28 crash near Urda, which killed 69 people.
Railway unions warn that the disaster may reveal wider problems across the network. A Renfe high-speed train hit a stationary Iryo train on the Madrid–Seville line. The crash derailed carriages and sent wreckage down an embankment.
Authorities say the line’s LZB train-protection system failed around 8:30 a.m. This left human controllers in Madrid responsible for managing trains on the affected part of the line. According to the government’s timeline, a controller later allowed the Renfe train to move again at normal speed while the Iryo train remained stopped.
The Iryo driver had told the control center that the train could not restart. The collision occurred at about 8:53 a.m. A judge and a rail-accident commission are investigating.
Investigators have retrieved the trains’ data recorders for examination. Transport Minister Óscar Puente blamed what he called a poor decision by a controller. But the cause has not been conclusively established.
Unions argue that the inquiry should also examine worsening working conditions, including fewer controllers handling heavier workloads. Their concerns come amid renewed scrutiny of the Madrid–Seville line. A separate crash there in January killed 46 people.
Spanish authorities continue to investigate the sequence of events. The final findings are expected to clarify whether procedural or wider system failures contributed to the disaster.