An area of almost 1.5 million square kilometres continues to be blanketed by smog in northern China.
The hardest hit zones are the cities of Beijing and Tianjin, and Hebei and Shandong provinces.
For two weeks, Beijing’s air was labelled worse than “very unhealthy” and “hazardous”.
According to the Chinese Academy of Sciences, 800 million people – over half the country’s population – are affected by the polluted air.
In Beijing, authorities have closed over 100 factories and taken 30 percent of government vehicles off the roads, but these measures have had little effect.
The problem stems from China’s use of coal – it burns almost as much as the rest of the world combined. With more economic growth, China’s use of coal is set to increase.
Chinese news agencies report that an online petition has been started by Beijing residents sick of the smog. It calls for a ‘Clean Air Act’ and has been signed by thousands of people.