Horrifying damage is being wreaked by one of the largest gorse fires in recent years in Northern Ireland, Stormont's Environment Minister Edwin Poots has said.
Firefighters are spending a second day in the Mourne Mountains, battling the flames through demanding terrain.
The blaze in the Slieve Donard area started in the early hours of yesterday morning.
The Northern Ireland Fire and Rescue Service has declared a "major incident" and the public has been urged to stay away.
The NIFRS said over 100 firefighters and 12 appliances continued to battle "one of the most challenging gorse fires firefighters have ever had to deal with".
As the sun starts to set on a long, hard day for our Firefighters and our partners we want to thank all of them for their hard work in the major incident in the Mournes. The incident is ongoing and will continue into tomorrow.
— Northern Ireland Fire & Rescue Service (@NIFRSOFFICIAL) April 24, 2021
📷@ConorK_Photohttps://t.co/FuUQNot1Ji pic.twitter.com/qfUotGQrxE
It is also using Coastguard helicopters to "achieve an aerial view of the fire, inform tactical firefighting decisions and transport firefighters to remote locations to tackle the fire".
Aidan Jennings, Assistant Chief Fire & Rescue Officer, said: "We are making good progress. However, it has been a challenging and exhausting day for everyone involved. Every firefighter on the mountain has been working exceptionally hard and I want to pay tribute to them."
First Minister Arlene Foster said on Twitter: "This is devastating and tragic. The impact on wildlife and flora is unimaginable."
This is devastating & tragic. The impact on wildlife and flora is unimaginable. Full support to those battling the flames. @NIFRSOFFICIAL https://t.co/ThhlTJVR5d
— Arlene Foster #WeWillMeetAgain (@DUPleader) April 23, 2021
Mr Poots said horrifying damage is being done over a wide spread area, particularly to wildlife and biodiversity.
He met emergency responders at the major incident command centre in Newcastle.
Mr Poots commended all involved in the effort to stem the fire, which is expected to continue across the day.
"This should not be happening, it is a time of the year when there is a lot of dry grass about, and people need to be ultra cautious that they don't accidently start a fire like this," he said.
"And for those who do it deliberately - you are doing massive damage to the environment, to biodiversity and to wildlife."
He said the area could take years to recover from the damage.
Britain's Northern Ireland Secretary Brandon Lewis described the scenes as "deeply distressing" at one of the region's most beautiful landmarks and paid tribute to the fire fighters at the scene.
Deputy First Minister Michelle O'Neill said her thoughts are with the firefighters and urged people to avoid the Slieve Donard area.
Thoughts with the firefighters back on the Mournes this morning battling one of our worst ever wildfires
— Michelle O'Neill (@moneillsf) April 24, 2021
I have asked executive colleagues for an update on response and I would echo calls for public not to gather in the area & request that walkers avoid Slieve Donard pic.twitter.com/ajf5Kk7C9Y
South Down MP Chris Hazzard said the local community is both shocked and angry at the impact on a popular spot with visitors, particularly after the impact of the coronavirus pandemic.
He said hundreds of thousands of visitors flock to the area every year.
Mr Hazzard described seeing the smoke yesterday, but then watching the wildfire escalate later after winds saw it spread rapidly towards Slieve Donard.
"People will have seen the shocking images, the Mournes last night looked like a range of volcanos that were erupting," he said.
"There was shock, but also anger in the community that here we are again, another event we have to deal with. Obviously they have been dealing with Covid-19, but there was also a large flood last year and now we're going to have to pick up the pieces after the fire."
SDLP MLA Colin McGrath said the fires highlighted the need to develop an all-island strategy to address the matter.
"With courageous fire crews tackling the blaze from early Friday morning there was a hope that the fire could be contained," he added.
"However, with some light winds it unfortunately managed to spread down the eastern slope of Leganabruchan and eventually into Donard Forest in Newcastle."
He added: "Having met with the NIFRS it is clear that they are doing everything they can to combat these blazes.
"However, the issue of gorse and wildfires is something that affects our entire island and our response to it cannot just be a reaction to every outbreak of fire but a measured response that attempts to understand why these fires are happening so often and ultimately to prevent them.
"That over the last four years we have had three years with continuous fires tells me we need to act now for the health and wellbeing of all our people," he said.
NIFRS are currently escalating firefighting operations in the Mourne Mountains. A large number of resources will be in attendance. We would kindly ask members of the public not to gather in the immediate area and request that walkers avoid the Newcastle side of Slieve Donard. pic.twitter.com/A46RXImCjC
— Northern Ireland Fire & Rescue Service (@NIFRSOFFICIAL) April 24, 2021