Raging forest fires in northern Thailand are threatening to worsen the country’s air pollution, which has sent nearly 2 million people to hospitals with respiratory illnesses since the beginning of the year.

Prime Minister Prayuth Chan-ocha on Thursday ordered urgent steps to put out forest fires in Nakhon Nayok province to the east of Bangkok and those in the country’s northern region including popular tourist destination Chiang Mai and Chiang Rai, according to government spokesman Anucha Burapachasri.

Firefighters and other officials have been deployed to monitor the affected areas, as burning of farmlands and illegal foraging occur during this time of the year, Anucha said in a statement on Thursday.