Day-trippers are being asked to stay away from the Tollymore Forest area.
A major operation is in place to deal with a forest fire now in its second day.
Around 60 firefighters are battling the blaze and trying to bring it under control.
The fire started in the forest around the Drinnahilly Mountain area of Tollymore Forest Park.
A Northern Ireland Fire and Rescue Service spokesperson said: “Firefighting will be continuing throughout the day and we would ask the public to avoid the Tollymore Forest area.”
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