JAKARTA, Indonesia -- Forest fires burning throughout Indonesia have prompted six provinces to declare a state of emergency and deploy thousands of security forces, a disaster official said Thursday
Firefighting measures included aerial water drops in anticipation of worsening forest fires that each year spread health-damaging haze across much of Southeast Asia, said Agus Wibowo, the National Disaster Mitigation Agency spokesman.
He said several fires detected on Sumatra and Borneo islands by weather satellites led to very poor air quality in six provinces with a combined population of more than 23 million.
Authorities have deployed nearly 6,000 personnel to douse the fires that have razed more than 30,000 hectares (74,130 acres) of forest and land in the provinces of South Sumatra, Riau, Jambi on Sumatra island and West Kalimantan, South Kalimantan, Central Kalimantan provinces on Borneo island.
The agency said satellites have detected 94 hotspots, with the biggest numbers in Riau province. The efforts involve 17 helicopters dropping 61 million liters (16 million gallons) of water.
Pekanbaru, the capital of Riau province, has been blanketed in smoke with a visibility of less than 4 kilometers (2 1/2 miles). More than 27,600 hectares (68,200 acres) of land and forest has burned out in the province alone, including in some parts of the Tesso Nilo National Park, home to about 140 endangered wild elephants, said local police chief Kaswadi.
The haze is an annual problem for Southeast Asia. Record Indonesian forest fires in 2015 spread haze across a swath of Southeast Asia and, according to a study by Harvard and Columbia universities, hastened 100,000 deaths.
Fires are often started by smallholders and plantation companies to clear land for planting. Many areas of Indonesia are prone to rapid burning because of the draining of swampy peatland forests for pulp wood and palm oil plantations.