This is the frightening scene that residents living near a forest witnessed as a large grass fire burned into the night.
Fire crews were back again at Mynydd Machen in Caerphilly little over 48 hours since they were first called to the hillside.
During the weekend, crews tacked flames that ripped through the forestry close to Machen village.
More than 30 hectares of mountainside were damaged in the blaze - leaving trees scorched and piles of ash behind.
On Monday night (April 26) , fire crews were back at the scene again.
A spokesman for South Wales Fire and Rescue Service said: "Crews are in attendance at a large grass fire in Machen, Caerphilly. We would ask local residents to keep all windows and doors closed at this time and thank them for their continued support and patience when we deal with this incident."
Photos show the glow of hot flames burning brightly on the hilltop above homes in Graig View, Chatham Street and Llanarth Street.
Local resident Paige Manley said: "The whole mountain is dotted with fires, the smoke is glowing a bright orange across the whole mountain and you can see the flames amongst the trees.
"There’s been ash falling in my garden all weekend and the smell is awful.
"It’s devastating seeing it’s up in flames, it’s such a beautiful mountain with lots of different walking and mountain biking routes but that’s all now been destroyed."
Several residents said the blaze was the same one from the weekend, which looks to have re-ignited again.
Fire crews had been previously called to the mountain on Friday evening, just hours after putting out a fire there on Thursday night.
The incidents prompted the fire service to issue a warning saying grass fires were "irresponsible and unacceptable" and calling on members of the public to "avoid putting further strain on Wales’ emergency services" at a time of increased pressure.
Gwent Police also said they were called to a number of grass fires in Torfaen, Caerphilly and Blaenau Gwent earlier this week.
Officers said on social media that they had been working with South Wales Fire & Rescue Service to use drones to increase patrols in the area following multiple incidents.
"Deliberately setting grass is irresponsible and unacceptable, but at a time of increased pressure, we need to work together and avoid putting further strain on Wales’ emergency services," added the fire service spokesman.
"We would urge anyone who has information on suspected deliberate fires, or who sees anything suspicious to contact 101, or call Crimestoppers anonymously on 0800 555 111. If you see a fire, or anyone starting a fire, please call 999 immediately."
