Key commuter train lines into Leeds are blocked due to a fault on a train.
As of 8.15am this morning (Wednesday) trains from Manchester Victoria via Brighouse and via Halifax are unable to run into Leeds.
This means commuters coming into the city from New Pudsey and Bramley will be delayed.
People travelling from Bradford Interchange and Halifax will also be delayed.
Northern Rail has said disruption is expected until 10am.
Northern Rail released a statement on Twitter at 8.15am which said: "Due to a fault on this train at Sowerby Bridge some lines are blocked.
"Train services running through this station may be cancelled, delayed or revised. Disruption is expected until 10am.
In a separate section headlined 'our advice to customers', the statement added: "Due to a fault on the 06.37 Manchester Victoria to Leeds, all services from Manchester Victoria via Brighouse and via Halifax, in this direction only, are currently unable to run.
"There is no current estimated time for service resumption."