KUALA LUMPUR, Malaysia (AP) _ Haze blanketed large parts of Malaysia on Wednesday, forcing schools to close, and experts warned smoke clouds from hundreds of forest fires in the region would only worsen the air pollution

The haze and smoke have also covered Indosia's Sumatra and Borneo islands _ where fires have burned unchecked for days _ as well as Singapore and southern Thailand, and there were fears of a repeat of a 1997 air pollution crisis.

In Malaysia, schoolchildren were sent home or stopped from playing outside, and some street sweepers wore masks over their noses and mouths to protect them against the smoke.

Environmental groups said they had received complaints of eye and throat irritation problems in some areas, including the northwest tourist island of Penang.

Plantation owners in neighboring Indonesia sometimes use fire as a cheap _ and illegal _ means of clearing land, mainly during the midyear dry season.

Hariyadi, an official at Indonesia's Meteorological and Geophysics Agency, predicted that the problem would get worse.

``The haze levels will rise because the fires have coincided with the dry season,'' said Hariyadi, who like many Indonesians uses only one name. ``There is no major rain expected.''

In Kuala Lumpur, the haze has been made worse by fires which have smoldered in layers of peat southwest of the city for four days.

The Malaysian government has refused to release current readings of the index it uses to measure air pollution, fearing tourists will be scared off. But the Environment Ministry on Monday banned open burning, a move required by law if the air pollution index rises above 100 points, which indicates unhealthy levels of suspended particles in the air.

In 1997, fires raged out of control for weeks during the dry season blanketing Singapore and parts of Malaysia and Indonesia with thick smoke. The ecological disaster also sparked a huge diplomatic row between the nations affected.