UK: Anomaly on the track spotted before train derailment near Lewes

Wednesday 19 August 2026 - 13:21

British investigators have identified a railway irregularity in surveillance footage recorded just before the derailment of a passenger train that occurred last week in southeastern England. The accident left two people seriously injured and raises questions about the state of the railway infrastructure.

Anomaly visible before the accident

An irregularity in the geometry of the track was already noticeable in the surveillance footage taken immediately before the derailment, the Rail Accident Investigation Branch (RAIB), the UK body responsible for investigating rail accidents, reported on Wednesday.

The anomaly was located in immediate proximity to the area where the train left the tracks.

This discovery represents a significant new element for investigators, who are seeking to accurately determine the circumstances that led to the accident.

The train derailed near Lewes

The accident occurred on August 13, when a passenger train operated by Southern derailed near Lewes, in southeastern England.

The derailment necessitated the intervention of emergency services and caused significant disruptions to the local railway network.

Two people were seriously injured in the accident.

However, the exact circumstances remain to be established, and the identification of a track anomaly alone does not determine the definitive cause of the derailment.

Investigators examining the state of the infrastructure

The RAIB continues its analysis to understand the nature and evolution of this irregularity.

The investigations will aim to determine whether the observed defect played a direct role in the derailment, as well as to verify the maintenance and monitoring conditions of the affected track.

The study of surveillance footage is one of the elements allowing investigators to reconstruct the final moments before the accident.

An investigation that could go beyond just the train

The focus of the investigation is therefore not solely on the rolling stock.

The state of the track, maintenance operations, inspections conducted before the accident, and monitoring procedures may also be examined.

The goal will be to determine whether the irregularity was significant enough to be detected before the train's passage and whether existing control measures should have allowed for intervention.

Answers still awaited

The discovery announced by investigators represents a major lead, but it does not yet constitute an official conclusion on the cause of the derailment.

The RAIB will need to compare the surveillance footage with the train's technical data, the state of the track, and other elements collected on site.

The definitive conclusions will help determine potential responsibilities and, most importantly, identify measures that could prevent a similar accident from occurring on the British network.