Network Rail have confirmed that 1,000m of cable has been stolen from the line between Bedford and Bletchley.
A spokesman told ITV Anglia that rail delays would continue for the rest of the day while engineers worked to make repairs.
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After a dry and sunny start, the cloud will build this afternoon and there'll be a few showers later.
Many places will have a fine day with some sunshine tomorrow but there will be a few showers about during the afternoon.
Norwich City manager Alex Neil has confirmed that the club have suspended Lewis Grabban after the striker went AWOL earlier this week.