About 1.43 million students from 12,874 schools were studying remotely in six provinces due to wildfire smoke, according to Indonesia's Education Ministry. ^[1] Mount Sinabung in North Sumatra erupted earlier this week, spewing a thick column of ash about 3,500 meters above its summit and forcing hundreds of people from their homes. ^[2] The Indonesian Ministry of Transport confirmed that flight operations at Kualanamu International Airport in North Sumatra are proceeding normally following an eruption of Mount Sinabung. ^[3] Authorities raised Mount Sinabung's warning from Level II (Watch) to Level III (Alert) following increased volcanic activity. ^[4] A thin layer of volcanic ash was detected in the aircraft parking area at Kualanamu International Airport on September 1, 2026, prompting a temporary closure of flight operations. ^[5] Flight operations at Kualanamu International Airport were temporarily closed on September 1, 2026, based on NOTAM A3250/26, and subsequently reopened based on NOTAM A3254/26 and NOTAM A3251/26. ^[6] Lukman F. Laisa, Director General of Air Transport at the Ministry of Transport, stated on September 4, 2026, that no volcanic ash was detected at the airport based on paper tests conducted on September 2, 2026. ^[7] Based on Significant Meteorological Information (SIGMET) from the Darwin Volcanic Ash Advisory Centre (VAAC), Mount Sinabung erupted on September 2, 2026, with a volcanic ash cloud reaching an altitude of 14,000 feet. ^[8]