Indonesian police have arrested 72 people suspected of deliberately starting forest and peatland fires as massive blazes across the country’s central and western regions generated dense smoke, disrupted visibility and sent hazardous haze across the border into Malaysia.
The arrests, announced Sunday, mark an intensification of Indonesia’s efforts to identify those responsible for fires that have become an annual environmental and public-health challenge. Authorities said the suspects are being investigated in connection with dozens of forest and land fires across several provinces on the islands of Borneo and Sumatra.
Mohammad Irhamni, director of special crimes at the National Police’s Criminal Investigation Agency, said investigators were examining 89 forest and land fire cases across five provinces on Borneo and another four cases on Sumatra.
Many of the suspects are accused of intentionally setting fires to clear land for plantations at a lower cost, he said.
“Plantation owners and traditional farmers often start fires to clear land for farming,” Irhamni said during a news conference in Jakarta.
Authorities, however, are looking beyond those who allegedly started the fires. Investigators are examining financial records to establish whether companies or other commercial interests financed, ordered or otherwise facilitated the burning of land.
“We will not stop at the perpetrators on the ground,” Irhamni said. “We will determine who benefited from these activities and who was ultimately behind them.”
The investigation could therefore widen significantly if authorities establish links between individual suspects and plantation companies or other businesses.
The suspects face charges carrying penalties ranging from substantial fines to prison sentences of as long as 15 years, according to police.
The government has repeatedly warned that deliberately setting fires to clear land can cause extensive environmental damage, particularly when flames spread into peatlands. Peat fires can continue burning beneath the surface even after visible flames have disappeared, making them particularly difficult to extinguish and allowing smoke pollution to persist for extended periods.
Indonesian President Prabowo Subianto travelled Saturday to Central Kalimantan, one of the provinces most severely affected by the fires, as authorities stepped up efforts to contain the spreading haze.
More than 7,600 hectares of land have burned in Central Kalimantan, according to authorities.
During his visit, Prabowo promised that the government would provide the personnel and equipment required to suppress the fires, including helicopters and water pumps. He also pledged action against companies found to have contributed to illegal burning.
“I hope we can control this soon,” Prabowo said during the visit. “We have experienced worse forest and land fires in the past, and we were able to overcome them.”
The president’s visit underscored the seriousness of the situation as Indonesia confronts a combination of dry weather, elevated fire activity and peatland conditions that can cause fires to spread rapidly and remain difficult to extinguish.
Prasetyo Hadi, head of the State Secretariat, who accompanied Prabowo, said at least four companies in West Kalimantan were under investigation for allegedly using fire to clear land.
If the companies are found to have deliberately started the fires, they could face sanctions including the revocation of their operating permits, he said.
The investigation represents an effort to move beyond prosecuting individuals found physically setting fires and establish whether businesses have benefited from illegal land-clearing practices.
Indonesia’s Environment Ministry recorded more than 3,700 hotspots on Borneo on Sunday, highlighting the scale of the ongoing fire activity.
Borneo is the world’s third-largest island and is shared by Indonesia, Malaysia and Brunei. Indonesia administers roughly three-quarters of the island, including extensive areas of forest and peatland.
The worst-affected Indonesian provinces include West Kalimantan, Central Kalimantan and South Kalimantan, where fire activity has increased in recent days.
Suharyanto, head of Indonesia’s National Disaster Management Agency, said peatlands were making the situation more difficult.
“Fires that appear ‘extinguished on the surface’ may still contain embers underneath, so sufficient rainfall is crucial to rewet the peat and fully suppress the fires,” he said.
The warning is significant because simply extinguishing visible flames may not be enough to end a peat fire. Burning material can remain underground and reignite when conditions become dry and windy.
Authorities therefore face the dual challenge of suppressing active flames and ensuring that underground peat remains sufficiently wet to prevent fires from returning.
The situation was not confined to Borneo.
South Sumatra, in western Indonesia, was also battling widespread fires, with the Environment Ministry reporting more than 1,700 hotspots on Sunday.
The fires generated thick haze and sharply reduced visibility in some areas. In parts of the province, visibility fell to only about 10 metres, according to the ministry.
Such conditions pose immediate risks to road users, aviation and communities living close to the fire zones. Prolonged exposure to smoke from forest and peat fires can also cause respiratory and other health problems, particularly among children, older people and those with existing vulnerabilities.
Indonesia has therefore deployed significant aerial resources as it attempts to contain the fires before they intensify further.
Cloud-seeding operations resumed over Kalimantan on Sunday in an effort to encourage rainfall in affected areas. Authorities also deployed 30 helicopters for water-bombing and aerial patrol missions across Kalimantan.
Another 22 helicopters were operating over Sumatra.
The aircraft are being used both to locate fires and to attack them from the air, particularly in areas that are difficult for ground crews to access.
Indonesia’s current fire emergency has been aggravated by an intensifying El Niño pattern and a prolonged dry season.
El Niño can alter rainfall patterns across Southeast Asia, leaving parts of Indonesia significantly drier than normal. When rainfall decreases and vegetation and peatlands dry out, fires can spread more quickly and become substantially harder to control.
Indonesia regularly experiences forest and land fires during dry periods. Some fires are accidental, but authorities have long struggled with the deliberate use of fire to clear land because it can be substantially cheaper and faster than mechanical clearing.
The practice has repeatedly caused domestic environmental crises and international diplomatic tensions.
The resulting smoke can travel hundreds of kilometres, crossing national borders and affecting neighbouring countries, particularly Malaysia and Singapore.
Malaysia has already experienced severe smoke from the Indonesian fires, with the eastern state of Sarawak among the areas hardest hit.
The Sarawak government said one district recorded “very unhealthy” air quality on Friday, while eight other districts registered unhealthy readings.
The deteriorating air quality forced authorities to close nearly 600 schools, affecting approximately 200,000 students.
The closures demonstrate how the Indonesian fires can have consequences far beyond the areas where they originate. Smoke carried across the borders of Borneo can affect Malaysian communities, schools, transportation and public health.
Cross-border haze has been a recurring source of tension between Indonesia and its Southeast Asian neighbours. Governments in the region have repeatedly called for stronger measures to prevent fires and hold companies accountable when land-clearing activities cause widespread pollution.
The latest episode could therefore renew pressure on Jakarta to demonstrate that the fires are being addressed not only as a domestic environmental emergency but also as a regional problem.
For Indonesian authorities, one of the most important aspects of the current investigation will be determining whether commercial interests played a role in the fires.
Police have already arrested dozens of individuals accused of setting fires, but investigators are examining financial transactions and other records to determine whether companies funded or instructed land clearing.
That approach could significantly increase the consequences for businesses if investigators establish evidence of deliberate burning.
The government has signalled that companies could lose their operating permits if they are found responsible.
For President Prabowo’s administration, the response also presents a test of its ability to enforce Indonesia’s environmental regulations while balancing the country’s large plantation and agricultural sectors.
Authorities must contain the immediate fires while addressing the economic incentives that encourage some landowners and farmers to use fire for clearing.
With thousands of hotspots still detected across Borneo and Sumatra, and peatlands continuing to smoulder beneath apparently extinguished areas, Indonesian officials face a race against time.
The government is relying on arrests, investigations, aerial water-bombing, patrols and cloud-seeding to bring the fires under control. But without sufficient rainfall, officials warn that the underground fires could continue generating smoke.
