Jakarta. The Environment Ministry has launched investigations into eight companies suspected of contributing to catastrophic floods and landslides that killed nearly 1,000 people across Sumatra, amid mounting evidence that extensive deforestation intensified the disaster.

Environment Minister Hanif Faisol Nurofiq said Monday that officials are questioning the companies as part of a process that could lead to administrative sanctions, environmental restoration costs, and potential criminal charges. The examinations began on Monday and continue through Tuesday. 

The Ministry has already suspended the operations of gold miner Agincourt Resources, state-owned plantation company Perkebunan Nusantara III (PTPN III), and North Sumatera Hydro Energy (NSHE), the developer of the Batang Toru hydropower plant. Investigators are also conducting on-site verification of four other companies.

“This clarification is the first step toward follow-up action,” Hanif told reporters in Jakarta. “We are not talking about permits. We are talking about environmental destruction and its impact on lives.”

Preliminary findings show large-scale forest conversion across five major watersheds — Batang Toru, Garoga, Badili, Aik Pandan, and Sibuluan — with roughly 340,000 hectares of forest altered for agriculture. Around 50,000 hectares of upstream forestland are now bare, significantly weakening the soil’s ability to absorb rainfall.

Hanif said the degraded landscape made the region highly vulnerable even to moderate rain. Over the past two days, an estimated 9.7 billion cubic meters of rainwater fell in Aceh, far beyond what the damaged terrain could contain.

Environmental group Walhi North Sumatra earlier accused seven companies operating in and around the Batang Toru ecosystem of contributing to the ecological collapse. The firms include Agincourt Resources, NSHE, Pahae Julu Micro-Hydro Power, SOL Geothermal Indonesia, Toba Pulp Lestari, Sago Nauli Plantation, and PTPN III.

In a parallel crackdown, the Forestry Ministry has sealed seven forestry-related facilities in North Sumatra linked to illegal logging and forest encroachment. Forestry Minister Raja Juli Antoni said five more timber sites remain under investigation.

“There will be no compromise for forest destroyers,” Raja Juli said.

Flash floods and landslides have swept through Aceh, North Sumatra, and West Sumatra since Nov. 25, destroying homes, bridges, and public infrastructure. The National Disaster Management Agency reported 950 deaths, 274 missing, and more than 156,000 homes damaged as of Monday.