Trains heading from St Albans towards London have been disrupted this morning by what rail operator Govia Thameslink describe as an “operational incident”.
Thameslink services running from St Albans City to London St Pancras may be cancelled or delayed.
The operator says services are expected to be delayed by up to 15 minutes.
Weekend services are already being disrupted in the wake of overhead wire problems during Thursday's heatwave.
UPDATE: Disruption related to this incident has now ended.
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