Army bomb disposal officers are on the scene of the huge North Yorkshire fire at Langdale Moor today (Thursday).
It’s because of fears that the heat could set off munitions.
The area of the blaze – which covered 5 sq km yesterday – encompasses an old army range.
Eleven fire engines and three argocat off-road vehicles are at the scene, near RAF Fylingdales.
A helicopter is also being used to douse the flames with water.
In an update today (Thursday), a North Yorkshire Fire & Rescue Service spokesperson said: “Farmers and local businesses have been assisting at the scene and we would like to thank them for all their help.
“No cause has been established at this time.
“There is still a lot of smoke in the area so we would advise people nearby to keep their doors and windows closed.
“The incident is on an old army range and we are aware that there are munitions in the area.
“We have precautions in place for our crews at the scene, but people may hear explosions. Explosive Ordnance Disposal are aware and are attending.”
The service says crews are likely to remain at the scene for the next few days, because “the fire is deep-seated in peat”.