BEIJING (Reuters) - Blue skies returned to Beijing on Thursday after overnight winds blew away the dangerously high levels of pollution that had blanketed the Chinese capital for five days prompting a pollution red alert.
The air quality index (AQI) in Beijing spiked to more than 400 overnight, but by morning had dropped to about 50.
Red alerts are issued when the AQI is forecast to exceed 200 for more than four days in a row, 300 for more than two days or 500 for at least 24 hours.
The Beijing city government said it had lifted the red alert, meaning emergency restrictions on vehicle use and construction would come to and end.
However, high readings are still being recorded in other parts of northern China, including in parts of the major metropolis of Tianjin which sits next to Beijing, and the province of Hebei that surrounds Beijing. [nL4N1EG1SV]
Twenty four cities had issued red alerts and the widespread pollution had disrupted flights, traffic and shipping, and closed factories and schools across northern China.
China began a "war on pollution" in 2014 amid concerns its heavy industrial past was tarnishing its global reputation and holding back its future development.
Reporting by Ben Blanchard; Editing by Michael Perry