Some trains to London this morning will be delayed Picture: SARAH LUCY BROWN (Image: Archant)
Some services between the two stations will be cancelled until midday according to Greater Anglia.
A tweet from the company said that a signal system fault between the two stations was causing the problem.
Greater Anglia are putting together a bus replacement service for trains that will be cancelled by the fault.
Among those due to be cancelled will be the 8.54 Felixstowe to Ipswich service due in to Derby Road at 9.09.
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