Indonesia has dispatched almost 5,000 personnel to fight fires in Kalimantan as the dry spell continues across the western and central parts of the island, where hundreds of hot spots have been detected in recent days.

The National Disaster Management Agency (BNPB) said yesterday that it has deployed 2,492 and 2,363 personnel in west and central Kalimantan respectively.

The group includes soldiers, policemen, officers from the BNPB and the Environment and Forestry Ministry, as well as local volunteers, said agency spokesman Sutopo Purwo Nugroho.

They were sent in after satellite data from the meteorology, climatology and geophysics agency, or BMKG, showed 536 hot spots across Kalimantan yesterday.

"BNPB has also deployed four water-bombing helicopters to focus on the area north of Supadio International Airport in Pontianak, West Kalimantan, to prevent the haze from affecting visibility for flights," said Dr Sutopo.

BMKG officer Giri Darmoko, who is based at the airport, said that due to the lack of rain in the past week, air quality has been deteriorating although it has not hit unhealthy levels. "Flights have not been affected because the haze has not travelled far from the hot spot areas such as Ketapang, Sintang and Sekadau," he said.

The dry spell in Kalimantan has led to fewer water bodies near affected areas, and water-bombing aircraft must travel longer distances to collect water, said Dr Sutopo.

"There are also no potential clouds to seed to induce rain above West Kalimantan and Central Kalimantan, where the weather is dry and therefore very prone to fires," he added.

Mr Giri said the fires are caused by "intentional burning of land" particularly near the border areas, where there are fewer patrols to curb slash-and-burn activities.