Of the total number, nearly 71 per cent, that is 34 hotspots, were found in North Sumatra Province, Slamet Riyadi, spokesman of the data section of the Pekanbaru meteorology station said here.
In North Sumatra, 16 hotspots were detected in Padang Lawas district, 15 in north Lawas and three from other regions.
Riau Province had nine hotspots comprising four in Bengkalis District, two each in Kampar and Rokan Hulu Districts, and one in Indragiri.
Wildfires in Riau gutted a total of 3,734 hectares of forest, peatland and plantations.
The Riau provincial police have detained 93 suspects for allegedly intentionally setting fires, presumably to clear land for farming.
Meanwhile, West Sumatra Province had five hotspots.