Klang and Putrajaya, as well as three areas in Sarawak, are in the very unhealthy air quality category as of 10am today.

According to the Department of Environment's tracking of the Air Pollutant Index (API), Kuching registered the highest API reading of 247, followed by Samarahan (219) and Sri Aman (219). 

In the peninsula, Johan Setia Klang also had a very unhealthy reading of 208, while Putrajaya is at 203.

A further 29 stations recorded "unhealthy" readings. There are 68 tracking stations nationwide.

This means that almost half of the stations in Malaysia are recording unhealthy API readings or worse.

The areas that were hardest hit are Sarawak and the southern states and west coast of Peninsular Malaysia, tallying with recent hotspot figures indicating that the source of the haze is from forest fires in the Indonesian regions of Kalimantan and Sumatra respectively.

An API of 0-50 represents good air quality, 51-100 is moderate, 101-200 is unhealthy, 201-300 is very unhealthy, while 300 and above is hazardous.

This comes as the Asean Specialised Meteorological Centre (ASMC) showed intensified hotspots in Indonesia.

According to the ASMC, as of yesterday, there were 274 hotspots in Kalimantan and 305 in Sumatra, none in Sabah and Sarawak and none in Peninsular Malaysia.

ASMC’s tracking has shown that the haze in Peninsular Malaysia is coming from Sumatra while the haze in Sabah and Sarawak is coming from Kalimantan.