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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Some early cloud possible but sunny spells breaking through readily in the morning, becoming prolonged by the afternoon.
The pilot, from the Gnat private display team died after the display aircraft he was in crashed near the CarFest event in Cheshire.
It will be a dry night but it will stay fairly cloudy, although the odd clear spell is possible.