By Somchai Samart
Thananchai Suwansuk, head of environment office of region six, said that 19 hotspots had been detected in Sumatra Island of Indonesia on Sunday, up from 12 spots on Saturday.
Among the four provinces, Songkhla has been hit the most from the rising level of dust less than 2.5 micrometres in diameter.
The wind has made it less severe in some areas, he said.
Officials plan to instal more devices to check air pollution in Pattani province.
In recent years, Thailand’s southern provinces have been affected by smog from Indonesia as forests there are cleared for agricultural activities besides regular forest fires.