Harbin, close to the Russian border, is the latest Chinese city to be plagued by severe air pollution.
A thick layer of smog has enveloped the Chinese city of Harbin, prompting local officials to close schools, cancel flights and take cars off the highways.
Home to 11 million people, Harbin is roughly the size of New York City. The smog was so thick on Monday that visibility in the city dropped as low as 10 meters.
The phenomenon has been dubbed "airpocalypse" by some commentators.
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