JAKARTA, Aug. 4 (Xinhuanet) -- Indonesia confirmed Thursday that forest fire in Sumatra island, which started Sunday, has blanketedpart of neighboring Malaysia.

Arbaini, head of Environmental Conservation of the Regional Environmental Impact Management Agency of Riau Province, said Thursday that the wind had carried haze resulted from hot spots inRiau and North Sumatra provinces toward Malaysia.

"From our monitor on the satellite picture, the fire starting from July 31 was sometimes up and sometimes down," she told Xinhuaby telephone.

However, she said that the fire had not yet caused serious impact on the provinces, adding, "We do not know the situation in Malaysia because the wind blows toward there, from southeast to east."

Arbaini attributed the fire cause to a seasonality of the dry season that lasts longer than previous ones.

To prevent further spread of the fire, Arbaini said that the authorities already have deployed teams to the scene of fire, and local companies also made efforts to stop the fire.

The haze slightly covered North Sumatra provincial airport but did not hamper the flight schedule, according to an official of the airport.

Forest fires frequently break out in Sumatra in dry season because of the spread of illegal land-clearing fires or carelesslydiscarded cigarettes.