JAKARTA — The number of fire hotspots across Indonesia more than quadrupled to 1,104 yesterday with Kalimantan bearing the brunt as prolonged forest and land fires generated smoke and haze, worsening air quality in several provinces.

The Forestry Ministry said the number of forest and land hotspots rose from 270 on Saturday, with Central Kalimantan recording the sharpest increase to 495 from 92 the previous day, while West Kalimantan rose to 174 from 22.

In a statement on social media, the ministry said the sharp increases followed several days of relatively low hotspot counts in Central and West Kalimantan despite ongoing firefighting operations.

A total of 61 aircraft remained deployed in the two provinces, including 44 for water bombing and 17 for aerial patrols and weather modification operations, it said.

Air quality deteriorated to very unhealthy and hazardous levels across much of Central Kalimantan, while West, South and East Kalimantan recorded unhealthy to very unhealthy conditions.

Central and West Kalimantan are among six priority areas for firefighting operations, alongside South Sumatra, South Kalimantan, Jambi and Riau.

“Joint teams continue to tackle forest and land fires through ground firefighting, water bombing, aerial patrols, as well as prevention and control measures in priority areas,” the ministry said.