MIRI: The Air Pollutant Index (API) in Kuala Baram has hit the unhealthy level of 123 on Wednesday morning (Feb 26).
In Miri, the API is at 97, which is at a moderate level but close to the unhealthy level which is an API of 100 and above.
Both districts are being badly affected by the haze from forest fires that have been burning at various plantations over the past three days.
Miri Fire and Rescue Department chief Supt Law Poh Kiong said the high API was from the smoke being emitted from the smouldering peat.
"The smoke is being emitted from the cluster of fires burning along the border of the land belonging to Naim Cendera and Shin Yang," he said
Both are private land development consortiums.
"Efforts are being carried out to douse the smouldering peat," added Law.
Law thanked members of the public who have been sending drinks and food to the firefighters battling the fires.
Firefighters are struggling to stop the fires following a dry spell in the northern part of Sarawak.