Liverpool Street Station (Image: (c) copyright citizenside.com)
Greater Anglia are cancelling or altering some services between Norwich and London because of a safety inspection being carried out on the track.
A problem has developed between Diss and Norwich which is affecting some Intercity services.
Most services into Norfolk will still travel through Suffolk and terminate at Diss instead, while some will make additional calls at Stowmarket.
However the 6pm Norwich to London Liverpool Street and the 8.30pm service in the opposite direction have both been cancelled.
The rail operator has said disruption is likely to continue until 11.30pm.
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