Passengers travelling between Peterborough and Ipswich have been told the service will be suspended until further notice.
Greater Anglia announced today at 6.34am that due to a train fault the vital route across Cambridgeshire and Suffolk would not be running.
They said: "We are sorry if your journey has been affected by this disruption.
"Passengers from Ipswich to Peterborough and from Peterborough to Ipswich are advised to travel via Cambridge."
However, at 8.30am Greater Anglia announced that due to a broken down train at Elmswell there would be disruption via Cambridge too.
A bus replacement service is now in place between Ipswich and Cambridge which will call at all scheduled stops.
They added: "Tickets will be accepted on Cross Country and East Midlands services between Cambridge, Ely and Peterborough in both directions.
"Please allow extra time for your journey."
The train service have not yet specified what the fault is between Peterborough and Ipswich but disruption is expected to last throughout the day.
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