Pictures showed smog so thick that buildings in Changchun, the capital of Jilin province in the northeast, were rendered invisible.
One image showed a restaurant's neon sign seemingly floating in mid-air above traffic, proclaiming in yellow: "Northeastern Dumpling King".
An image circulating online showed a man biking through snow in Shenyang, capital of the neighbouring province of Liaoning, yesterday wearing a vintage-looking gas mask, and the official news agency Xinhua quoted a hospital official in the city saying that his respiratory ward had been overwhelmed, with all its beds full.
The World Health Organisation's recommended maximum is a 24-hour average of 25 micrograms.
"Today's haze is pretty severe and choking - when I walked out the door I thought someone's house was on fire," said one poster in Changchun on China's Twitter-like Sina Weibo.
The Changchun city government said on social media it was initiating a "level three" emergency response, telling schools to stop organising outdoor activities, and reminding residents to stay indoors and "take health precautions", without further specifications.
PM2.5 particulates can play a role in heart disease, stroke, and lung ailments such as emphysema and cancer.
Online commentators were furious.
"If heating companies dare to buy cheap, low-quality coal and pollute the environment, they should be discovered and immediately shot," said one poster.
Overall levels of PM2.5 particulates reached 1,157 micrograms per cubic metre in Shenyang yesterday, data from the city's own environmental protection bureau showed.
They peaked as high as 1,400 in parts of the city according to state broadcaster CCTV, with visibility less than 100 metres.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →
Smart Quarterly
₹900
3 Months
₹300/Month
Smart Essential
₹2,700
1 Year
₹225/Month
Super Saver
₹3,900
2 Years
₹162/Month
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors


Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share


Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor


Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements


Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
