Train delays and cancellations affecting services across the disctirct could continue until this afternoon, it is understood.
Rail staff at Leeds station have informed passengers that the services may not begin running again before 12 o'clock.
A "trespass incident" at Leeds has left all services running out of Leeds have either been delayed, revised or cancelled.
There is a police presence around Leeds station and passengers are not even allowed access to platforms.
Passengers waiting to board at both Westgate and Kirkgate should check train times, along with Castleford, Glass Houghton, Knottingley and the Pontefract stations.
It is thought the disruption will continue until at least 9.15am.