The agency's Terra and Aqua satellites had detected 310 hotspots in South Sumatra, followed by 96 in Lampung, 86 in Jambi, 35 in Bangka Belitung, and one in Bengkulu.
On Thursday, the BMKG had detected 405 hotspots across the island.
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Head of the BMKG Pekanbaru station Sukisno confirmed that the number of hotspots in Riau had reached 15, of which 10 are located in Indragiri Hulu District, four in Indragiri Hilir District, and one hotspot in Kuansing District.
Of the total hotspots, 10 are confirmed to be forest fires, with eight in Indragiri Hulu and two in Indragiri Hilir.
Haze has blanketed Pekanbaru City on Friday morning.
Related news: Haze impairs visibility to 700 meters in Pekanbaru
"Smog is observed in Pekanbaru City, with visibility reaching two kilometers," he stated.
Land and forest fires are still detected in the Pekanbaru suburb of Air Hitam and also in its neighboring district of Kampar.
Local residents have been inhaling the smog since Wednesday, especially in the morning and at night.
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Related news: Terra, Aqua satellites identify 1,182 forest fire hotspots in Sumatra EDITED BY INE