Smoke from wildfires in Indonesia has drifted across to neighbouring Malaysia to envelop several cities in an unhealthy haze. Officials blamed the smog on more than 300 "hot spots" on the Indonesian island of Sumatra -- separated from peninsular Malaysia by the narrow Straits of Malacca.
According to Asmah Ibrahim, director of the Malaysian environment department's air division, preliminary tests show that Kuala Lumpur, Penang and some other cities had unhealthy air.
During each dry season, fires set illegally by Indonesian and Malaysian farmers to clear land are blamed for the haze that clouds skies in parts of Southeast Asia. In 1997-1998, such fires in Indonesia's Sumatra and Kalimantan provinces went out of control for weeks, destroying 10 million hectares and blanketing Singapore and parts of Malaysia and Indonesia with thick smoke. The ecological disaster sparked a diplomatic row, with economic losses estimated at around us $9.3 billion. It also prompted a 2002 agreement to fight pollution from forest fires.