Rail services have been suspended due to a fire at a factory near the railway line.
East Midlands Railway and Greater Anglia have both paused services running between Norwich and Ely due to a fire at Attleborough.
Norfolk Fire and Rescue said it was dealing with a large fire in the area of Maurice Gaymer Road.
Greater Anglia said it had been told the factory building involved housed gas cylinders and/or chemicals.
It said the blaze was causing large amounts of smoke and urged local residents to keep doors and windows closed.
In a statement on its website, Greater Anglia said: "As a result, we are unable to run train services through the area on the advice of the fire brigade, due to the factory housing gas cylinders/chemicals.
"Train services will be disrupted as a result.
"We are in the process of acquiring buses to operate between Norwich and Ely."
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