A "complete loss of signalling" has left the East Suffolk Line, which runs between Ipswich and Lowestoft, blocked.
Greater Anglia tweeted that the line had suffered a "complete loss of signalling" and that the "train service is suspended".
They later updated their website, saying that the issue was between Ipswich and Saxmundham, and that additional trains will be running from Saxmundham to Lowestoft.
They added that "Network rail engineers are currently en route to the major signalling sites".
The 9.05am Lowestoft to Ipswich was cancelled at Melton. It was due to arrive at Ipswich at 10.31am.
The 10.05am Lowestoft to Ipswich and the 10.08am Ipswich to Lowestoft are have both been cancelled. The 11am Lowestoft to Ipswich is terminating at Saxmundham.
Great Anglia has advised those who need to travel from Lowestoft to Ipswich or London to travel via Norwich, and vice versa.
The 10.35 Lowestoft to Norwich will be missing Brundall Gardens, but will divert to Ipswich after stopping at Norwich.
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