Grass fires: Three arrested after night of deliberate blazes
Three teenagers have been arrested after a 20-hectare (50 acre) blaze on a mountain above a village in the Rhondda Valley.
The man, 19, a 17-year-old boy and 16-year-old girl were stopped in a car on the A4059 at 04:45 GMT on Tuesday.
They were arrested on suspicion of arson with intent and are in custody.
It comes after the fire on the mountain above Ton Pentre - one of a number of deliberately started grass fires on Monday.
"The fires are putting lives and people's health at risk," South Wales Police said on Facebook.
On Tuesday, firefighters returned to the scenes of a number of grass fires, which had been started the day before.
In all, South Wales fire service attended 15 blazes, including on the the mountain above Ystrad in the Rhondda, where there were dramatic scenes as flames and smoke filled the sky behind homes.
There were also wildfires on Llantrisant Common, in Talbot Green, and at Cymmer Hill, in Maesteg.
And the service monitored a blaze near Llechryd, at the top of the Rhymney Valley, near the A465 Heads of the Valleys road.
The largest incident was between Ystrad and Pentre, in the Rhondda Valley.
More than 25 firefighters were called, along with specialist off-road vehicles. The fire was first reported just before 19:00 BST
Another large grass fire was reported at Caerau, Maesteg just before 20:00
Firefighters have also returned to the scene of a blaze which began on Llangynidr Mountain, Tredegar.
In north Wales, the emergency services were called to a large mountain fire in Denbighshire on Monday evening.
Some 300 sq m of forestry was burned in the incident at Coed Pen-y-garth, Glyndyfrdwy, near Corwen.
Four fire crews attended the incident at 20:47 on Monday.
They extinguished the flames with hoses and beaters, declaring it over at 22:41.
South Wales fire service said it had attended 307 deliberate grass fires between 1 March and 20 April but that figures were down on last year.
In the same period for 2019 they went to 394.
The service said it attended 15 grass fires on Monday, 11 suspected to be deliberate.