Jakarta. Indonesian authorities have arrested 44 people suspected of starting forest and peatland fires that are spreading health-damaging haze across the region, officials said Wednesday.

Forest and peat fires are an annual problem in Indonesia, straining relations with neighboring countries. In recent years, smoke from the fires has blanketed parts of Indonesia, Singapore, Malaysia, and southern Thailand.

The fires are often started illegally by plantation owners or traditional farmers to clear land for planting, said Suharyanto, head of Indonesia’s National Disaster Mitigation Agency, or BNPB, in a statement Wednesday.

“The forest fires are not caused only by drought but also by humans,” said Suharyanto, who, like many Indonesians, uses a single name. “Hopefully these arrests will serve as a deterrent to the public to stop setting fires to clear land.”

Police presented the suspects, including a woman, during a news conference Tuesday in Pekanbaru, the capital of Riau province. The suspects, handcuffed and wearing orange prison uniforms, could face prosecution under Indonesia’s environmental protection law, which carries a maximum 10-year prison sentence for setting fires to clear land, Suharyanto said.

He urged the public to support the government’s campaign to prevent human-caused fires and to report anyone found setting fires to clear land.

Thick haze continues to blanket parts of Riau province, with Rokan Hilir and Rokan Hulu districts among the worst affected. Fires have burned around 500 hectares (1,235 acres), reducing visibility to less than one kilometer (about half a mile).

In response, the government has stepped up efforts to control the fires by deploying cloud seeding operations to induce artificial rain in Riau since Tuesday, with plans to continue through July 25, Suharyanto said.

The latest arrests are not the first tied to Indonesia’s ongoing fire crisis. In 2019, police arrested 230 people linked to forest fires.

Forest fires on Sumatra and Borneo islands often break out during dry spells, sending haze over neighboring Singapore and Malaysia. In 2023, Indonesia, which frequently issues apologies to its neighbors over the haze, denied that its fires were responsible for pollution blanketing Malaysia.