A broken down train between Retford and Doncaster is causing delays of up to 60 minutes.
This is expected to continue until noon.
Further to this on Tuesday, September 6, extensive damage was caused to the overhead wires between Retford and Doncaster.
All lines have now reopened allowing trains to run, however, disruption is expected to continue until end of service.
Journeys between Grantham and Doncaster and throughout the East Coast Main Line may be cancelled, diverted or delayed by up to 20 minutes as services return to normal.
Some trains from London towards Doncaster will not call at Retford. Customers for Retford should change at Doncaster for a returning service to Retford.