Derailed wagon was dragged through Barking station

C2C A freight wagon sits off the rails beside a railway track under overhead power lines. A detached set of train wheels on its axle lies across the ballast in the foreground, with broken sleepers and loose cables nearby. A line of shipping containers, one yellow and the rest red, stretches back along the track towards tower blocks.C2C
A set of wheels broke off from the wagon, causing track damage

A derailed freight wagon was dragged for almost a mile and through an east London station, according to a preliminary investigation into the incident.

The Rail Accident Investigation Branch (RAIB) said one wagon of a GB Railfreight container train came off the tracks near Barking station at 13:04 BST on 23 October.

The resulting damage to the tracks and points caused forced part of the c2c line to shut for nearly three weeks. The freight train had been travelling from London Gateway in Essex to Hams Hall, Warwickshire.

The RAIB has said its investigation will look at how the wagon derailed, how the train was loaded and prepared, the design of the wagons and the state of the track.

The train had been travelling at around 8 mph (13 km/h) when it stopped briefly and the wagon derailed as the train moved off again.

The train then carried on for about 0.7 miles (1.1km), with the wagon's wheels running along the sleepers and through platform eight at Barking station. It stopped after a signaller noticed faults on several sets of points.

No-one was injured.

c2c said engineers had to repair more than 1.2km of track. They also rebuilt points that were damaged beyond repair and replaced severed signalling equipment and cabling.

While the work went on, c2c trains did not call at Dagenham Dock, Rainham or Purfleet. Passengers were told not to travel and replacement buses ran between Upminster and Grays.

Services resumed on Wednesday, along with London Overground trains on the Suffragette line between South Tottenham and Barking Riverside.

Rob Mullen, of GBR Anglia, which runs c2c, praised staff for their efforts "given the scale of the recovery required".

GBR Anglia has not said whether freight trains serving the ports of Tilbury and London Gateway are back to normal.

The RAIB will publish its findings when the investigation ends.

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