Three labourers at a pine resin factory in Almora died of burn injuries they sustained while dousing a forest fire that had reached close to their factory, an official said on Friday.

Another labourer injured in the incident is still under treatment, the daily bulletin issued by the forest department said giving data of the damages caused by forest fires in the state over the past 24 hours.

All the labourers were from Nepal and not part of the designated fire fighting teams, a forest official in Almora said.

They received burn injuries while struggling to quell the blaze in Gananath range of Almora forest division near their factory on Thursday and were under treatment at the base hospital, Almora, the official said.

A report from Nainital said smog has engulfed the tourist town as a result of the raging forest fires.

Air pollution is also on the rise which may cause health problems among residents.

It may aggravate problems of patients already suffering from asthma and bronchitis, doctors said.

Dr MS Dugtal, senior physician at a government hospital, said air pollution can increase asthma and lung problems in children as well as the elderly.

The smog which was visible everywhere from Nainital to Haldwani can be risky, he said and advised people suffering from respiratory problems, like chronic bronchitis and asthma, to take their medicines regularly and avoid going out unless necessary.

Dr Dugtal also advised people to use air purifiers in their homes and face masks while going out.

According to the data, 64 new incidents of forest fire were reported from different parts of the state over the last 24 hours in which 74.67 hectares of forest land were destroyed.

Since November 1 last year, there have been 868 fire incidents in Uttarakhand in which more than 1,000 hectares of forest land have been destroyed.

Of the total fire incidents, Kumaon has reported 456 and Garhwal 344, the forest fire bulletin said.