A major UK railway line remains partially closed because of a large fire, disrupting thousands of journeys.

National Rail said some lines of the west coast mainline were blocked between London Euston and Watford Junction because of the blaze in Camden, north London.

The London Fire Brigade (LFB) said it was alerted to the fire at 9.31am on Friday. It said: “At the height of the fire, a single-storey commercial building and most of a neighbouring property were alight.”

It said no injuries were reported and the cause of the fire was under investigation.

The brigade sent 10 fire engines and about 70 firefighters to the scene in Regent’s Park Road.

William Selas, 40, said earlier on Friday that he could see a lot of fire and smoke from his bedroom window. “Oh my God, I saw so many firefighters come around. Hopefully it’s going to be all right and we won’t have to leave the house or run away.”

The incident was causing disruption to Avanti West Coast, London Northwestern Railway, London Overground and Southern services. Avanti West Coast services to London were reportedly held at stations as far as Warrington, Cheshire.

Some affected passengers were able to use their tickets on alternative routes.