Four passengers and four members of railway staff were unhurt when a Northern unit was derailed between Lancaster and Barrow-in-Furness early today.

The line will be closed for some time yet, while inspectors from the Rail Accident Investigation Branch gather evidence.

Although the cause of the accident is not yet known, Network Rail said that the area was ‘extremely wet’, and that engineers have discovered a void in the ground that had opened around 150m from the derailment, which occurred near Grange-over-Sands station at about 06.00 this morning.

Network Rail’s North West route infrastructure director Chris Pye said: ‘All lines through this area remain blocked, meaning trains are currently unable to run between Barrow-in-Furness and Lancaster.

Northern regional director Craig Harrop added: ‘We're working closely with Network Rail and others to understand more about what happened.

‘No trains are running between Barrow-in-Furness and Lancaster and there will be significant disruption to our services in this area.’