Passengers faced lengthy delays of around four hours after electrical cabling burst into flames near a train station in Oldbury.
The electric cables affecting signals near Langley Green train station, Oldbury, caught fire at around 4.50pm on Thursday.
This affected train signals between Birmingam Snow Hill and Stourbridge Junction stations, forcing Network Rail to halt a number of London Midland and Chilton Railways services.
Replacement coaches were put into service, and investigations were underway to establish a cause of the blaze.
West Midlands Fire Service press officer, Station Commander Dean Harris, told the Express and Star: "Investigations are ongoing to establish the cause of the fire. We have to assume it was due to an electrical fault."
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