Jakarta – Fire has ravaged 11,569 hectares of plantations and commercial forests in Riau province over the past month, a local environment expert said in the provincial capital of Pekanbaru on Thursday.

"The damaged plantations and forests are in the districts of Siak, Rokan Hilir, Bengkalis, and Dumai," said Mangandar S.P. of the provincial office of the Environmental Impact Management Agency (Bapedal), as quoted by Antara news agency.

As of early this month, at least 51 hot spots were still found in Bengkalis and the islands of Riau, he said, adding that the hot spots were detected in the plantation areas of PT Budidaksa Dwi Kesuma, PT Makmur Platindo Nusantara and PT Panuasurya Agrosejahtera, and in the forest concession areas of PT Arara Abadi and PT Rimba Rokan Lestari.

"All these companies are in Bengkalis," he said, noting that an investigation team would soon be sent to observe the affected areas.

Asked whether the protected forest of Bukit Batu had caught fire, he said that it was difficult to verify but one of the nearby plantations was reportedly ablaze.

A report from the Bengkalis-based environmental agency said that about 150 hectares of Bukit Batu forest had already been affected by fire.