It is the third day since the fire began in the peat bog in Tak Bai district of Narathiwat.
An airborne survey by paramotor glider found smoke from the fire covering a section about 25 kilometres long on Sungai Kolok-Tak Bai Road. There were five hotspots destroying about 160,000 square metres of the forest that adjoins Ban Plak Pla in Khosit sub-district of Tak Bai.
Unlike last year, when there was a similar fire, there was no official action to contain the outbreak.
It was believed the fire was accidentally spread by villagers who intentionally tried to burn a part of the forest to clear it for growing rubber trees. The fire was also destroying some local rubber plantations.