Smog Situation: were greeted by thick smog on Monday morning forcing a lot of them to wear facemasks to prevent inhaling the dirty air.

People wearing masks became a common sight in inner areas of the capital today.

The pollution continued to remain at harmful levels for the fourth straight day today [Monday] and the situation was likely to remain critical for at least another month due to weather patterns, experts said.

This was not regular winter fog but a deadly cloud of fine dust particles and other air pollutants, according to China-based air-pollution monitoring website http://aqicn.org.

The site reported that the PM2.5 air-quality index (AQI) in Bangkok this morning reached a peak of 183, an unhealthy level, while some areas such as Bang Khen district were at hazardous levels, with PM2.5 AQI at 396.

The site forecast that Bangkok would face harmful levels every morning for the rest of the week because there was little wind.