Passengers hoping to travel from Scarborough to Malton, Leeds and beyond have been told to expect major disruption this morning because of a trespass incident.
All services from Leeds station are suspended and British Transport Police has Tweeted: "No trains running at this time. Working with other agencies to resolve this. Thank you for your patience."
A statement said: "All lines in and out of Leeds station are currently suspended.
"Due to an ongoing incident involving the emergency services, all trains to and from Leeds are suspended.
"At this stage we don't have an estimate for when trains will start running again."
TransPennine Express, which runs the services between Scarborough and Leeds has said: "We are unfortunately advising customers not to travel until further notice due to the severity of disruption."
National Rail Enquiries has estimated that it will be at least noon before services resume.
Services on the Yorkshire coast line between Scarborough, Bridlington and Hull are not affected.