Singapore's haze condition continues to deteriorate, with strong smoking smell choked the whole city state on Monday afternoon.

The three-hour Pollutants Standard Index (PSI) climbed further to 150 as of 6 p.m. lcoal time, according to Singapore's National Environment Agency (NEA). However, the real condition is very likely to be much worse as the visibility obviously deteriorates every 15 minutes.

Most residents have been staying indoors, with many wearing masks on street. There's an acrid smell of burning in the air, which can even be smelled inside with all windows closed. The smog is heavy, with buildings opposite the street barely seen.

Singapore has been haunted with haze problem for years.