Three pupils and a man cover their faces with scarves and masks in Wuhan on Thursday as the city's air pollution reached a hazardous level in Central China's Hubei province. The main pollutant, PM 2.5, is reportedly caused by the burning of straw by farmers in the areas surrounding Wuhan. Chinese Premier Li Keqiang declared “war" on pollution in March at the opening of the annual meeting of National People's Congress with the government unveiling detailed measures to tackle what has become a hot-button issue. [Photo by Jin Siliu/Asianewsphoto] 

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