"The number is much less than on the previous days," Tri Puryanti, an analyst of Pekanbaru meteorological, climatology and geophysics agency (BMKG), said here on Saturday.
Of the 21 hot spots, five were found in Jambi, 13 in Riau, one in North Sumatra, and two in Bangka Belitung.
On Thursday, the satellite detected 25 hot spots in Sumatra, including 22 in Riau Province, a drastic drop from 142 hot spots on Wednesday.
The 142 hot spots in Riau were found earlier in 11 districts and cities, namely 35 in Rokan Hilir District, 25 in Pelalawan, 23 in Indragiri Hilir, 14 in Siak, 12 in Bengkalis, 10 in Indragiri Hulu, nine in Rokan Hulu, six in Kampar, four in Dumai, three in Kuantan Singingi, and one in Pekanbaru.
In addition to fire control efforts on the ground, the National Disaster Mitigation Agency (BNPB) made a weather modification over Riau and sent water bombs to extinguish the fires by using the Indonesian military`s helicopters.
KR-FZR (f001 )