Malaysia has declared a state of emergency in the country's south after choking smog from slash-and-burn agriculture in neighboring Indonesia enveloped the region.
Residents in Muar and Ledang districts of Johor state have been told to stay indoors. This comes after a similar order in Singapore last week.
Smog from Indonesia is a perennial problem in Malaysia and Singapore, but the pollution levels this year have hit record levels. The fires in Indonesia are set by palm oil producers clearing jungle for new planting.
Malaysian officials on Sunday said the Pollution Standards Index in Muar and Ledang had topped 700, more than twice the 300 level considered dangerous.
It's gotten to the point the smog has become a political and diplomatic issue, straining relations between Indonesia and its neighbors.
The BBC says:
"Schools in the region have been ordered to remain closed. Local authorities have distributed face masks to residents.
Even in Kuala Lumpur, where smog levels have so far remained moderate, visibility is now strongly reduced and the smell of thick smoke hangs in the air, correspondents say.
Kuala Lumpur resident Raj Ahmed told the BBC: 'You wake up in the morning and you can smell burnt wood - you look out the window and there is constant smog clouding the major landmarks that you would ordinarily see.
'If you go outside, it's like constantly standing close to a small barbecue.'"
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