BORNEO — Indonesian authorities detained 12 suspects linked to alleged arson and illegal land clearing as wildfires on Borneo generated a transboundary haze crisis that drifted into Malaysia. The fires have prompted school closures, flight delays, and reduced visibility across the region.

Central Kalimantan Police Chief Iwan Kurniawan stated that investigators have detained 12 suspects linked to alleged arson and illegal land clearing in the past week. "Every forest and land fire incident in Central Kalimantan is investigated," Kurniawan said.

The haze has severely impacted daily life and infrastructure in affected areas. Smoke from the fires contributed to traffic accidents and delayed several flights, while haze in parts of Kalimantan reduced visibility to 1 meter to 10 meters in some areas. Motorists in affected areas were forced to drive with headlights on during daylight hours due to smoke, and residents, including schoolchildren, wore masks while walking outside in affected areas.

Malaysia’s eastern state of Sarawak has been among the areas hardest hit by the haze. One district in Sarawak recorded 'very unhealthy' air quality on Friday, while eight others posted unhealthy readings. Poor air quality in Sarawak prompted the closure of nearly 600 schools, affecting about 200,000 students.

Indonesia’s Forestry Ministry recorded more than 5,000 hot spots on the Indonesian portion of Borneo. Nationwide, the ministry detected 11,908 hot spots in the previous 24 hours, up from 6,352 a day earlier. The total area burned in Indonesia this year has reached about 285,000 hectares.

Forest-monitoring platform Nusantara Atlas reported that about 182,000 hectares burned in July alone. The area burned in July was nearly double the area scorched during the first half of the year. An intensifying El Nino pattern and a prolonged dry season have fueled the fires, according to Indonesia’s National Disaster Management Agency.

Forestry Minister Raja Juli Antoni visited fire-hit areas near Palangka Raya on Wednesday. "Whoever they are, big or small, without exception, anyone who destroys nature and forests will face strict legal action," Antoni said. Indonesian authorities warned they would take legal action against anyone who starts an open fire. Authorities state that fires are often started illegally to clear land for plantations or agriculture.

Why It Matters

The fires are concentrated on Borneo, the world’s third-largest island shared by Indonesia, Malaysia, and Brunei. Indonesia occupies about three-quarters of Borneo. Indonesia regularly experiences transboundary haze during severe fire seasons, particularly when peatlands on Sumatra and Kalimantan burn.

Historical data indicates the scale of emissions during similar weather patterns. During the strong El Niño in 1997 and 1998, wildfires in Indonesia emitted as much as 2.5 gigatonnes of carbon dioxide into the atmosphere. During another strong El Niño in 2015, wildfires in Indonesia emitted an estimated 1.5 gigatonnes of CO2.

Timeline

On 2026-08-21, wildfires on Borneo and elsewhere in Indonesia created haze that drifted into Malaysia.

What's New

A study titled "Life after logging: reconciling wildlife conservation and production forestry in Indonesian Borneo" was published in 2005 in Center for International Forestry Research (CIFOR) eBooks. Research titled "Governance of Waste in Indonesia: Implementing Policies and Role of Local Authorities" was published in 2023 in Journal of Indonesian Scholars for Social Research. A study titled "Three Indonesian Clusters of H5N1 Virus Infection in 2005" was published in 2006 in New England Journal of Medicine.

Research titled "4. The Role and Identity of Religious Authorities in the Nation State: Egypt, Indonesia, and South Africa Compared" was published in 2010 in Varieties of Religious Authority.

How Sources Differ

Regarding the topic of study titled indonesian published, Center for International Forestry Research (CIFOR) eBooks notes that a study titled Life after logging: reconciling wildlife conservation and production forestry in Indonesian Borneo was published in 2005 in Center for International Forestry Research (CIFOR) eBooks. Regarding the topic of titled published journal indonesian, Journal of Indonesian Scholars for Social Research notes that research titled Governance of Waste in Indonesia: Implementing Policies and Role of Local Authorities was published in 2023 in Journal of Indonesian Scholars for Social Research.