Both Pekanbaru and Medan flight schedules were disrupted as visibility dropped to as little as 700 meters in the thick smoke, which made conditions too dangerous for landing. Some flights from Aceh to Medan were diverted to Kuala Lumpur, and regional flights within Sumatra were also canceled.
Other regional airports at Pinangsori and Silangit were also closed, and Indonesian carrier Wings Air canceled several flights as a result of the poor visibility.
The haze, caused by fires lit deliberately to clear rainforest and peatland for plantations, has caused disruptions and health problems as far away as central Malaysia and Singapore.
Reports indicate that as many as 1,000 fires were blazing out of control across the Riau region in Sumatra, aggravated by a recent unseasonal month-long dry spell that has created highly combustible conditions.
The latest data show that fires have spread across 7,972 hectares of land, but northeasterly winds have helped disperse the haze in recent days.