PETALING JAYA, Malaysia - The number of areas with an unhealthy air pollutant index (API) increased from five on Tuesday evening to six yesterday morning.

Three areas in Sarawak - Bintulu, Miri and Samarahan - recorded unhealthy readings of between 104 and 137 while Batu Muda, Kuala Lumpur, had a reading of 102.

Two areas in Selangor - Kuala Selangor and Port Klang - had readings of 117 and 125.

Forty areas, or 81% of all locations, recorded moderate air quality compared to 41 on Tuesday.