Travel disruption caused by a fire near tracks linked to London Euston was expected to continue on Friday night.
Firefighters scrambled to the blaze in Camden at 9.31am on Friday.
Plumes of smoke could be seen coming from a building that sits on top of several rail lines, next to Regent's Park Road Bridge.
Shortly after 11am, National Rail warned disruption could be expected for passengers between London Euston and Watford Junction following the blaze.
Camden fire latest: Roads closed and trains delayed
Other affected routes included Avanti West Coast between London Euston and Birmingham New Street, Liverpool Lime Street and Manchester Piccadilly.
Roads were also closed as crews tackled the fire and there were no reports of any injuries.
But in a post on its website last updated at 4.27pm, National Rail said Avanti West Coast services running between London Euston and Watford Junction may be cancelled, delayed by up to 30 minutes or revised.
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It added disruption was expected until the end of the day.
It followed an earlier warning for major disruption up until 5.15pm.
But Southern services would no longer be affected by the disruption, it added.
(c) Sky News 2026: Camden fire: Travel disruption continues after fire near rail tracks
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