Indonesia is stepping up efforts to combat forest and peat fires across Kalimantan as worsening haze, poor visibility, and unsuitable cloud conditions hamper aerial firefighting operations.

The Air Pollution Standard Index at the Jekan Raya station in Palangka Raya, Central Kalimantan, surged to 3,540 at 3.59pm yesterday, far exceeding the hazardous threshold of 300.