Problem with signals between Diss and Norwich has seen trains cancelled or delayed.
A fault with the signalling system has meant that Greater Anglia trains have been forced to run at reduced speed on the line towards Norwich this morning.
Services running between the two stations have been experiencing delays of up to 60 minutes.
Disruption is expected to continue on the mainline services between Norwich and London until at least early afternoon.
A number of services have been cancelled including the 11.02am train from London Liverpool Street and the 1pm and 2pm journeys from Norwich to London.
Earlier this morning the 8.30am and 10.30am Norwich to Liverpool Street trains were also cancelled, while the 9.03am service began from Ipswich rather than Norwich.
- For up-to-date information visit Greater Anglia Journey Checker
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