Shocking footage shows a thick blanket of killer smog engulfing Bangkok this morning as officials warned it had become a serious threat to health.

The pollution cloud, a deadly mix of fine dust particles and other air pollutants, has been carpeting the Thai capital for three days. It is EIGHT TIMES higher than the safe limit.

The smog has been caused by increasing numbers of cars on the road, an explosion in construction projects funded by China, and stagnant weather conditions.

Witsanu Attavanich, associate professor of economics at Kasetsart University, said: ''Air pollution is really a silent killer and many Thais underestimate the danger to their health, so not many people protect themselves by wearing a facemask or installing air purifiers at home.''

Visibility in some parts of Bangkok was reduced to just 1km while air quality levels rocketed past the safe zone.

The PM2.5 air-quality index (AQI) in parts of Bangkok reached a shocking 394 microgrammes per cubic – far past the acceptable limit of 50.

Mr Attavanich said he country would face billions of baht in additional health costs unless the severe air pollution was tackled.

Shocking footage shows a thick blanket of killer smog engulfing Bangkok this morning as officials warned it had become a serious threat to health.

The pollution cloud - a deadly mix of fine dust particles and other air pollutants -
has been carpeting the Thai capital for three days. It is EIGHT TIMES higher than the safe limit.

The smog has been caused by increasing numbers of cars on the road, an explosion in construction projects funded by China, and stagnant weather conditions.

Health experts have warned that the pollution is a ''silent killer'' and that at current levels was extremely harmful to anyone stepping outside. They said the cost of treating people could run into ''millions of dollars''.

Witsanu Attavanich, associate professor of economics at Kasetsart University, said: ''Air pollution is really a silent killer and many Thais underestimate the danger to their health, so not many people protect themselves by wearing a facemask or installing air purifiers at home.''

Visibility in some parts of Bangkok was reduced to just 1km while air quality levels rocketed past the safe zone.

The PM2.5 air-quality index (AQI) in parts of Bangkok reached a shocking 394 microgrammes per cubic - far past the acceptable limit of 50.

Mr Attavanich said he country would face billions of baht in additional health costs unless the severe air pollution was tackled.