Firefighters have been called to a fire at a business on the main road between Lancaster city centre and the M6.
The call-out on Friday morning was to a building on the Dennison Trailers site on Caton Road.
A Lancashire Fire and Rescue Service spokesperson said: "We currently have six fire engines attending a commercial building fire on Caton Road, Lancaster.
"Please avoid the area and consider alternative routes.
"If you can see or smell smoke, please keep your doors and windows closed. Thank you."
The call out came at 10.39am.
Six fire engines and an aerial ladder platform from Lancaster, Morecambe, Bolton-le-Sands, Hornby, Fulwood and Chorley attended.
"Firefighters are using breathing apparatus, one hose reel jet and a ground monitor to tackle the fire," said the spokesperson.
"Crews remain in attendance."


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