Mark Zuckerberg's Beijing smog jog chokes up Chinese social media

Facebook founder posts picture of himself running in Tiananmen Square when air pollution was 15 times safe level

A photograph of Facebook founder Mark Zuckerberg jogging through the smog in downtown Beijing has prompted a torrent of comments - not all of them flattering - on Chinese social media.

Zuckerberg, who is in the Chinese capital for an economic forum, posted the photo of himself and five others running through Tiananmen Square on Friday, with the gate to the Forbidden City imperial palace in the background.