A signal fault is delaying Greater Anglia trains on the main line between Norwich and London this evening.
Passengers travelling between Suffolk, Essex and London are being warned their trains may be cancelled, revised at short notice or delayed.
Services are running at a reduced speed on some lines because of a fault between Shenfield and Gidea Park and disruption is expected until at least 9pm.
Trains to and from Witham, Colchester, Manningtree, Clacton, Ipswich, Stowmarket, Diss and Norwich are being affected.
Passengers heading towards Ipswich and Norwich are being encouraged to use train services between Liverpool Street and Cambridge as an alternative route.
Elsewhere in Suffolk, services running between Ipswich and Lowestoft are also being affected by a signalling issue.
Train services running to and from Lowestoft may be cancelled, delayed or revised, Greater Anglia bosses said.
Disruption on this line is expected until around 10pm.
Both Greater Anglia and Network Rail have apologised for the disruption.
Updates for specific trains can be found via the rail operator’s JourneyCheck tool.
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