Air quality in Kedah has plunged to unhealthy levels in recent days because of smog from forest fires in neighbouring Indonesia.

A Department of Environment official said that the Air Pollution Index (API) at Bakar Arang in northern Kedah hit 104 early today.

The API index considers a score of 101-200 to be unhealthy.

And major western coast areas from Negeri Sembilan and Selangor to the northern states of Perak and Penang have inched closer to unhealthy air levels, the official said.

Blame it on Sumatra

The Meteorological Services Department said the haze was due to forest-burning in Sumatra, Indonesia.

"The haze is causing reduced visibility of less than 10 kilometers in some parts of central Selangor state to Penang," an official told AFP .

Parts of Indonesia's Sumatra island rose sharply to 262 (from 254 yesterday), adding that 16 hotspots were detected in Malaysia and 18 on Borneo island, which is shared between Malaysia and Indonesia.

Meanwhile, at least 68,000 farmers in Kedah state, a vital paddy production region in Malaysia, expressed concern that the haze may damage their crop.

"We are monitoring the situation closely and hope for some rain or strong winds to remove the haze," Ismail Arshad, chairman of the local farmers' association was quoted as saying by the New Straits Times newspaper.