Nightly News | December 07, 2013
>>> we're back with a healthy emergency tonight in shanghai. the chinese city with more than 17 million people has been suffering through the worst air pollution it has ever seen. our report tonight from nbc's ian williams .
>> reporter: the soaring skyline of mainland china 's commercial capital was little more than a smudge through the thick smog. the tallest buildings disappeared into the smog, many in the city were wearing masks. "i have difficulty in breathing" says 24-year-old zwei ji yu. "visibility is also bad and so is my mood." rising pollution levels record in shanghai that prompted the highest level of health warning. the concentration of the most dangerous particles reaching 20 times what the world health organization regards as hazardous. "i don't think it's fit for humans to live in this kind of environment" says this man. hundreds of flights were canceled or delayed, schools closed, residents urged to stay indoors and factories ordered to cut off production. ships forced to navigate cautiously through the haze. experts blame the cold windless weather for a cloud of pollution from cars, factories and coal burning that has sat over eastern china for most of the week, and there's been record-breaking levels in other cities, including beijing earlier this year. the government has announced many plans to fight the pollution but with little apparent progress. the dense smog in eastern china is starting to lift today but here in beijing it's starting to approach hazardous levels. the east and north of china are particularly vulnerable in winter, and we're really just getting into the coldest month. ian williams , nbc news, beijing .