Visibility of less than 165 feet affected cities from Beijing and Hebei in the north, to areas surrounding Hong Kong in the south.
Some official Communist Chinese media outlets were slammed by Internet users and other media after they tried to put a positive spin on the hazardous pollution.
The Global Times said smog could be useful in military situations, where it could hinder the use of guided missiles.
Broadcaster CCTV listed five “unforeseen rewards” of smog, including helping Chinese people’s sense of humor.
“Is the smog supposed to lift if we laugh about it?” retorted Beijing Business Today, published by the city government’s official Beijing Daily.
“Smog affects our breathing. We hope it does not affect our thinking,” the publication added.
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