Train services between Peterborough and Huntingdon stations may be delayed this morning due to an incident that is causing disruption.
Network Rail are currently on site at a location the two stations where a possible track fault has been reported.
A Network Rail spokesperson said: "Subsequently, we have been advised that animals may have caused a small amount of damage, but not causing any major issues.
"This is being confirmed as soon as possible, and we will resume our regular timetable as quickly as we can."
Disruption is expected to continue until 10.30am.
Great Northern/Thameslink has since issued advice to customers.
A spokesperson said: "Trains are being delayed when travelling from Peterborough towards Huntingdon.
"This affects Thameslink services on the Peterborough to Horsham route, as well as other operators' long-distance trains in the area.
"You can use your normal route, but please expect delays of around 20 minutes to your journey.
"This delay may change slightly for each individual train. You can see the status of the next train from your station here.
"You can also check if this is on your route by using the live map."
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