Forest fires which have been raging in Riau province, Sumatra since January are worsening due to the current heatwave plaguing the region. (AFP photo)

JAKARTA: Forest fires which have been raging in Riau province, Sumatra since January are worsening due to the current heatwave plaguing the region.

The current blaze has spread to over 1,136 hectares and is growing, and smoke is beginning to blanket the area, data from the Riau District Disaster Management Agency revealed today.

Indonesian authorities are currently struggling to douse the fires through methods such as water bombing, Bernama reported.

But fears are rising that the annual event, which is triggered by seasonal hot weather and exacerbated by open burning carried out by farmers, may bring about haze which had previously choked neighbouring Malaysia, Singapore and Thailand.

The Indonesian Meteorology, Climatology and Geophysical Agency said today that with winds of 10 to 27 kilometres per hour moving in a north-easterly direction, the smoke from Riau may move closer to the Asian mainland.