Smoke from raging ground and forest fires has blanketed Pekanbaru, the capital of Riau province on Indonesia's Sumatra island, local meteorology and airport officials said on Friday.

Marzuki, an offcial of the meteorology agency, said that the visibility had decreased to the range of 6 to 7 kilometers. The normal is from five to ten kilometers.

"This morning the visibility was extremely down to between 30 meters to 50 meters," Marzuki told Xinhua by telephone.

He predicted that the cause of the smoke was the burning of forest as part of land clearing to begin new plantations.

"If the burning of forest continues, it could significantly decrease the visibility to an extreme level," he said.

The observer of the weather of the city airport of Syarif Hidayatullah named Tarman Sembiring said that the haze had gradually begun to cover the city since two weeks ago.

"Obviously it disturbs the flights, but now it is not on that level which can delay the flight schedules," he told Xinhua.

"If there is no rain in a couple of days, it can seriously hamper the flight, as the smoke keeps gathering on the airport," he said.

The latest report on the fires released by the Indonesian Space and Aviation Agency on Wednesday showed that 139 hot spots found in Sumatra island and 120 of them were on Riau province. Seven others were in Kalimantan island.

The senior official at the local Environmental Impact Management Agency Arbaini said that dozens of fire fighters assisted by scores of nearby residents had been deployed since four days ago to battle the blaze, and now they nearly stopped all the spots of fires.

"There are two main fire locations, we have stopped one and now the team nearly completed their task on the second place," he told Xinhua.

She revealed that the cause of the smoke was the burning of forest, but her office was now investigating whether the activities were carried out by individual only or by private companies.

In 1997 and 1998, haze caused mainly by forest fires in the country covered parts of Southeast Asia for months, causing the region suffering losses of billions of U.S. dollars due to a disruption of air traffic and other activities.

Source: Xinhua