The air hanging over Thailand's far north has become so polluted, the prime minister went on Tuesday to see in person what is being called a severe health crisis.
Much of the current pollution has been caused by the burning of forest undergrowth by villagers to make it easier to gather mushrooms and other products for sale. The burning often occurs at night, lighting the sky but making it hard to catch the perpetrators.The problem has been worse this year because of a drier-than-usual dry season. In several weeks, farmers are expected to start burning corn fields to clear them for planting, prolonging the pollution.
There has been widespread criticism of the government's response so far, with about 40 000 people signing apetition calling for the governor's replacement. The local government has been hesitant to declare a state of emergency, in part because of the possible impact on tourism.