The fire service have responded to a blaze at Carnbane Industrial Estate in the outskirts of Newry.
The fire that began in the early hours of Friday morning is at one unit within the industrial estate.
Four fire engines attended the scene as well as two aerial appliances and a high volume pumping appliance.
A spokesperson for the Northern Ireland Fire and Rescue Service said: "Thirty eight firefighters are currently dealing with a significant fire involving wood products. The incident is likely to continue for most of today. The cause of the fire is under investigation.”