China smog shrouds Beijing and northern area
7 October 2013 Last updated at 15:59 BST
Beijing and a large area of northern China are shrouded in thick smog, as the country's extended holiday has come to an end.
It will take three more days for the sky above Beijing to clear, the Beijing News newspaper reported.
The smog has lead to flight cancellations and motorway closures, drastically reducing visibility in some areas, as this video shows.