Indonesia on Sunday said firefighters had extinguished all the fires on Sumatra island blamed for causing a choking haze which smothered the region.

The fires from land clearance in Riau province and neighbouring North Sumatra produced the haze which blew across to neighhbouring Malaysia and Singapore.

"All areas which had been set ablaze in land clearing practices to prepare for plantation, all these can now be said to have been extinguished. So the number of fire spots is now at zero," Forestry Minister Malem Sambat Kaban said on ElShinta private radio.

He said there may still be hotspots, areas of high temperature registered by satellite imaging, but they did not indicate surface fires.

"The problem now is that Riau is an area of peat," he said, adding that while the surface fires had been extinguished the peat could continue burning underground.

"And the more water you pour over it, the more smoke you get," in burning peat areas, Kaban said.

He said the local authorities, with the help of the military, police and several foreign teams, "are now very aggressive in extinguishing" the fires.

The radio said Riau province had in the past days formed a team of some 1,200 people to combat blazes there. They were further assisted by teams from several other countries, including Malaysia.

Kaban also said the blazes were caused by small farmers and plantations clearing non-forest land for planting, rather than forest fires.

"Do not forget that these fires are not in forests. Our forests are not on fire. These are land clearing of plantation areas," he said.

Choking haze

While the government banned the practice of using fire to clear land for farming or plantations, "the environmental awareness and commitment of the entrepreneurs are still low," he said.

Haze from smoke of the fires on Sumatra and the Indonesian part of Borneo island has enveloped Malaysia and Thailand this month, causing health and traffic hazards.

In 1997 and 1998 choking haze caused mainly by Indonesian forest fires enveloped parts of Southeast Asia, including Malaysia, for months, losing the region some nine billion dollars due to the disruption of air traffic and other business activities.

Malaysia on Monday deployed 125 firefighters to battle the fires on Sumatra while Singapore Tuesday said it would send a military plane equipped with cloud-seeding devices to the island.