The tractor was said to have breached the boundary of a nearby field late on Wednesday evening.
The tractor has now been removed from the line at Fitzwilliam, but Northern are warning passengers of disruption up until 6pm on Thursday, August 16.
Services in and out of Leeds, Wakefield, Sheffield and Doncaster, among others, are disrupted, with major delays in place.
For live updates, passengers are advised to visit www.northernrailway.co.uk/stations.
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