Malaysia has declared a state of emergency in two southern districts after choking smog triggered by forest fires in Indonesia reached hazardous levels.

The coastal towns of Muar and Ledang in Johor state are in shutdown as air pollution index in the area hit 750 on Sunday, more than twice the 300 level considered dangerous. It is the highest reading Malaysia has seen in 16 years, reports AFP.

Schools in the southern region remained closed and residents were advised to stay indoors.

In Kuala Lumpur, pollution also took a turn for the worse. The landmark Petronas Towers that graced the capital’s skyline was shrouded in thick smog.

Smog from Indonesia, set by palm oil producers clearing jungle for new planting, has been a recurring problem in neighboring Malaysia and Singapore especially during drier summer months. But the record pollution level has now become a political issue, and could strain relations between the Southeast Asian nations.

Malaysia’s environment minister will meet his Indonesian counterpart on Wednesday to discuss the haze problem, reports BBC.