Authorities closed 409 schools in Sarawak, on the Malaysian side of Borneo, on Tuesday due to haze Air pollution index reached unhealthy levels on Tuesday KUALA LUMPUR: Malaysia sent half a million face masks to the eastern state of Sarawak and closed more than 400 schools there on Tuesday as a haze spread from forest fires in neighboring Indonesia, officials said. Authorities in Singapore also said air conditions could reach unhealthy levels there over the next 24 hours if the wind kept bringing smoke from Indonesia, and advised anyone feeling unwell to seek medical attention. Forest fires have raged through parts of the Indonesian island of Sumatra and the province of Kalimantan on Borneo in recent weeks, forcing the government to send in thousands of military and police to douse the flames. Indonesia’s neighbors have regularly complained about smog caused by its forest blazes — often started by farmers trying to clear land for palm oil and pulp plantations. Authorities closed 409 schools in Sarawak, on the Malaysian side of Borneo, on Tuesday due to haze, the state education department said. Malaysia’s national disaster management agency (NADMA) said it had sent 500,000 face masks to the state, after the air pollution index reached unhealthy levels on Tuesday. One Sarawak district saw a “very unhealthy” pollution level of 201, while unhealthy readings were seen in five other Malaysian states on the country’s peninsular, the agency said. Southeast Asia has suffered for years from annual bouts of smoke caused by Indonesian farmers’ slash-and-burn practices, raising worries about health and the impact on tourism. Indonesia last week said it had detected haze crossing over from Kalimantan in Borneo to the Malaysian side on the island. But on Tuesday, its climate agency disputed findings by Malaysia and Singapore that the countries were also seeing smog from fires on Sumatra island. “As for transboundary haze, there has been none detected from the area of Sumatra toward the Malaysian peninsula,” the climate agency said. It added that signs of forest fires were also spotted in Malaysia, the Philippines, Papua New Guinea, Vietnam, East Timor and Thailand. Singapore recorded slightly hazy conditions on Tuesday due to persistent fires in Sumatra’s Riau and Jambi provinces, the country’s national environment agency said. “Given the air quality forecast for the next 24 hours, healthy persons should reduce prolonged or strenuous outdoor physical exertion,” the agency said. “Persons who are not feeling well, especially the elderly and children, and those with chronic heart or lung conditions, should seek medical attention,” it added.