A fault with the signalling system between St Albans and Luton means some trains may be cancelled or delayed.
Disruption is expected until 06:00.
Check before you travel:
You can check your journey using the National Rail Enquiries real-time Journey Planner
Twitter:
If you would like to follow this incident on Twitter, please use #StAlbans
Compensation:
You may be entitled to compensation if you experience a delay in completing your journey today. Please keep your train ticket and make a note of your journey, as both will be required to support any claim.
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