An inferno on a mountainside populated by ponies and other wildlife was likened to Mount Doom from Lord of the Rings by shocked onlookers.
The massive fire tore across the Snowdonia peak of Foel Dduarth on Monday afternoon in north Wales.
Fire crews attended the scene but later had to withdraw from the area because of the dimming light and rough terrain in the area.
One of the first at the scene was farmer Gareth Wyn Jones who described a scene of carnage where only recently dozens of rare ponies had been gathered for a health check.
He told North Wales Live. : “It looks like something you would see in the Lord of the Rings, it’s so big and fast-moving.
“The whole of the mountain has gone, it’s completely devastated.
“I don’t believe they (the ponies) would have come to any harm unless they got trapped in a pocket of fire.
“In all my years I’ve never seen a fire move so fast. It’s just unbelievable.
“We’ll have to wait until the morning to find out if it’s spread to other mountains nearby.
Some had speculated the blaze had been caused by controlled burning which was rejected by Mr Wyn Jones.
He added: ““The mountain is in an SSSI (Site of Special Scientific Interest), so burning is not allowed there. It may have been an accident, arson or an act of God.
“An accident, such as a discarded cigarette, is another possibility, as the area is heavily walked.
“The mountains are so wet at this time of year it’s hard to see how it could have caught hold.”
The blaze could be seen for miles around. John Riley, in Benllech , on the northeast corner of Anglesey, got a shock when catching sight of the fire through his partner’s French windows.
He had been readying for a trip to the gym when he saw the inferno.
He said: “I grabbed my camera because it looked pretty massive.
“The fire must have been 10-15 miles away but we could clearly see it.
“I’d estimate the line of fire was about one-and-a-half miles long. It looked like the whole side of a mountain was on fire.”
North Wales Fire and Rescue said on social media: “We are aware of a fire in the open in #Abregwyngregyn .
“Fire crews have been in attendance since 3pm but have since withdrawn due to hazardous terrain and darkness.
“Crews will re-attend in the early hours to reinspect.”
Many people expressed concerns for local wildlife, including the ponies who call the area home.
One said: “I hope all the animals, including the ponies are safe and well.
“Some were already at Horse Sense, Wirral to be cared for.”
Another added: “Can't belive that the mountain went up in flames like that after the rain we’ve had recently. Hope all the animals are safe.
“And all out there tackling the fire, stay safe all of you.”