(AFP) The Department of Environment today reported "unhealthy' air quality in five areas, partly due to forest fires in neighbouring Indonesia.

However it said the haze which has hit parts of the country for several days is expected to lift later this week.

A spokeswoman said burning by local cultivators had also contributed to the haze.

On Monday the department had imposed a total ban on open burning and warned that offenders could be jailed up to five years, fined RM500,000 or suffer both penalties.

Satellite images showed that hot spots -- areas showing high heat levels caused by burning -- in Indonesia's Sumatra island had fallen to 28 from 242 yesterday but had increased from eight to 15 in Sarawak.

She said the air pollutant index (API) at five stations, one in Penang, two in Selangor and two Sarawak, was classified as unhealthy.

'Confusing the public'

Air quality at eight other stations was good while 35 were moderate.

"We have been monitoring the readings and find that the API is quite stable and should come down in a day or two as we don't see any increasing trend," the spokeswoman said.

She declined to give specific readings, saying "we don't want to confuse the public with numbers".

The government decided in 1999 not publish API figures amid fears they would scare away tourists. But environmental groups have called for readings to be published daily.

"The people who are monitoring the situation are not telling us what the haze situation is like. We can only guess how bad it is," Meenakshi Raman, honorary secretary of environmental group Sahabat Alam Malaysia, told AFP .

Selangor Mentri Besar Mohamad Khir Toyo said open burning caused by the dry spell had caused pollution in several areas.

He advised residents in affected areas to stay indoors and told schools to halt outdoor activities.

Main culprits

The Sarawak Natural Resources and Environment Board said today it had identified oil palm plantations, mainly in Sibu and Bintulu, as the main culprits of illegal open burning.

Choking haze, caused by fires in Indonesia, enveloped the region in 1997 and to a lesser extent in 1998 and caused an estimated RM35 billion in economic losses.

Many of the fires were deliberately set by planters clearing land for cultivation.