Researchers from Harvard and Columbia universities in the US estimated there were more than 90,000 early deaths in Indonesia in areas closest to haze-belching fires, and several thousand more in neighbouring Singapore and Malaysia. The new estimate, reached using a complex analytical model by combining satellite data with models of health impacts from smoke exposure and readings from pollution monitoring stations, is far higher than the previous official death toll given by authorities of just 19 deaths in Indonesia. It triggered calls for action to tackle the “killer haze”.