Malaysia has closed 409 schools after forest fires caused a haze to descend on the eastern state of Sarawak.
The government said the haze was caused by smoke from neighbouring Indonesia, where over one thousand forest fires are burning on the islands of Sumatra and Borneo.
The Malaysian government has issued half a million face masks for residents in Sarawak.
Officials said that Sarawak district hit a “very unhealthy” 201 pollution level on Air Visual’s air quality index, while unhealthy readings were recorded in five other states in the country.
Air quality has to reach a rating between 201-300 to be designated “very unhealthy” on the index.
Honolulu in Hawaii, considered one of the cities in the world with the cleanest air, has an 8 rating on the index.
London, which struggles with air pollution, has a rating of 21, which is ranked as ”good”.
Singapore said its air conditions could also hit unhealthy levels over the next 24 hours, as winds blow pollution in from Indonesia.
An unhealthy ranking on the scale is anything over 151, with Singapore currently rated at 99.
The city-state advised residents feeling unwell to seek medical attention.
“Given the air quality forecast for the next 24 hours, healthy persons should reduce prolonged or strenuous outdoor physical exertion,” the country’s environment 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.”
Indonesia’s neighbours in southeast Asia have regularly complained about smog caused by the country’s forest blazes.
The fires are often started by farmers trying to clear land for palm oil and pulp plantations.
Indonesia has deployed thousands of emergency crews to combat fires at 1,600 hot spots, according to the AFP news agency.
The practice had previously caused officials to worry about a potential negative impact on the country’s tourism industry.
Indonesia denied Malaysia’s claim that the haze was caused by its forest fires.
Indonesia’s weather agency said it had detected more than 2,500 fires across the region.
Additional reporting by agencies
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