Passengers on train services between Norwich and London are facing delays and cancellations today due to damaged overhead cables.
Greater Anglia has warned that severe disruptions will continue through the rest of the day.
The news comes as thousands of mourners have been travelling to the capital to pay respects to the Queen, where she is lying in state at Westminster Hall until the state funeral on Monday, September 19.
A spokesperson for Greater Anglia said: "Due to extensive damage to the overhead electric lines between Manningtree and Ipswich, there is severe disruption to train services between London and Ipswich/Norwich.
"A limited replacement bus service is in place between Colchester and Ipswich.
"Customers are advised to expect delays and to allow longer times for their journeys."
Passengers have an option to travel to London via Cambridge to avoid replacement buses.
Network Rail engineers are currently working to complete the repairs "as quickly as possible" but Greater Anglia said the extent and nature of the damage mean that it is could take until the end of Friday before the work is finished and a normal service can be restored.
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