An official of the Pekanbaru Meteorological, Climatology and Geophysics Agency (MBKG) said here on Wednesday that 148 hot spots of forest and plantation fires were detected in Riau Province, Indonesia's Antara reported.

"Based on the monitoring by the US NOAA (National Oceanic and Atmospheric Administration) satellite, NOAA-18, there are 187 hot spots across Sumatra, and 148 of them are in Riau," the agency's forecaster Ardhitama said.

The hot spots were detected across 10 districts and cities in Riau, including in Pelalawan (20 hot spots), Rokan Hilir (32), Kampar (7), Kuantan Sengingi (1), Siak (1), Bengkalis (21), Idnragiri Hulu (8), Indragiri Hilir (18), Rokan Hulu (23), and Dumai (1).

Antara reported that the number of the hot spots in Riau increased to 148 from 106 on Tuesday, indicating that the forest and plantation fires in the province have spread to a wider area.

The fires have produced thick haze covering several cities including here.

"The haze is horrible. It has been quite thick since in the morning," a local resident, Ganda Wibowo, 23, said, adding that the haze has caused eye irritation and respiratory problems.