Young and old residents of the Chinese metropolis of Wuhan were advised to stay indoors on Monday after a thick haze blanketed the city of nine million people, official media said
Described by residents as opaque with yellowish and greenish tinges, the fug descended suddenly in the morning, prompting people to rush to put on face masks, witnesses told AFP.
Xinhua said straw burning was the cause and denied there had been any industrial accidents in or near Wuhan, after Internet rumours suggested there had been an explosion at a chemical complex northeast of the city.
But it quoted the environmental protection department saying industrial accidents were not responsible and analysis showed an increase in carbon particles from burning organic matter.
Source: Yahoo! News
As of now it looks like the Chinese environmental agency isn’t sure what exactly caused the mysterious haze but that it seems unlikely that it’s caused by any industrial accident. China has notoriously bad industrial pollution from coal burning power plants, increasing traffic and lax environmental protection measures. But when conditions are right, it can be extremely poor air quality. It seems like people are concerned that an industrial accident would NOT be reported. Regardless, their health is at risk from such pollution.
Update (18-Jun-2012) Now mushroom cloud. With additional info and video.