Thameslink trains are delayed between St Albans and London St Pancras. (Image: Archant)
All four lines between St Albans and London St Pancras International were closed earlier after overhead lines in Cricklewood were damaged.
Three of the lines have now reopened, but major disruption to trains between Luton and London St Pancras International is expected to continue until around 4pm.
Until then, trains may be delayed by up to 30 minutes, or cancelled.
To follow the incident on Twitter, use #Cricklewood.
For a full list of alternative bus and rail services with ticket acceptance, see:
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