Trains between Preston and Wigan North Western have been cancelled due to overhead wire problems near Euxton Balshaw Lane.Advertisement
A limited bus replacement service is running between Preston station and Wigan North Western.
Delays of up to an hour are being predicted for most passengers.
A tweet from Network Rail at 9.59am indicated engineers are on site but it will take a day to get repairs in place.
The incident was reported at 3.39am and since then passengers have been diverted via other routes.
A statement just before 6pm on Saturday from Network Rail said work on the line was progressing well and they hoped to complete the work by Saturday evening.
The West Coast main line services from and to London Euston have been diverted.
Trains from Glasgow Central are terminating at Preston and train services to Birmingham are being diverted via Manchester and Crewe.
Services from Euston are terminating at Warrington Bank Quay, and passengers with onward journeys are being advised to change at Crewe to make their journey.
You can get the latest on the National Rail website or follow the Twitter hashtag #PrestonWigan