Facebook CEO Mark Zuckerberg (front) takes a mask-free jog past Tiananmen Square in Beijing on Friday morning, smiling through thick smog. He came to Beijing to attend the three-day China Development Forum which starts from Saturday. Photo: AFP

 Facebook founder Mark Zuckerberg was dubbed by Chinese netizens "the most expensive air cleaner" after photos of him running by Tiananmen Square in downtown Beijing spread widely on social media on Friday, as he wore no mask despite visible smog.

Zuckerberg posted on Facebook a picture of him running with several people by the gate of the Forbidden City on Friday morning, saying, "It's great to be back in Beijing! I kicked off my visit with a run through Tiananmen Square, past the Forbidden City and over to the Temple of Heaven."

Access to the US-based social media platform is not available in the Chinese mainland, as with Twitter and search giant Google. But photos of Zuckerberg running in downtown Beijing have been circulated on the Chinese equivalents of social media platforms like the Sina Weibo and WeChat, with netizens cheering for or mocking the world-famous entrepreneur.

"How's the smog taste?" Weibo user "Xiaoshanzi" asked.

"He may regret his decision that day," wrote another netizen, "Sailor Gu."

Beijing has been going through the latest round of smoggy weather, with the PM2.5 reading on Friday morning lingering above 300, indicating serious air pollution.

But Zuckerberg and five others who ran along with him appeared to wear no masks.

"To get Facebook open in China, Zuckerberg has been fighting hard," another Chinese netizen wrote.

The tech tycoon is in Beijing to attend the China Development Forum, a three-day high-level meeting that will see Chinese and world business and political leaders attend.

Central bank governor Zhou Xiaochuan, Financial Minister Lou Jiwei and dozens of ministerial-level officials will attend the forum, titled "A China of the new Five-Year Plan era."

Former US secretary of state Henry Kissinger and many foreign bankers and economists will also join the meetings.

According to the forum agenda, Zuckerberg will join a dialogue with Jack Ma Yun, founder of China's e-commerce giant Alibaba, on Saturday morning, themed around creativity and development.

Zuckerberg, married to Chinese-American Priscilla Chan, is known as the "Chinese people's son-in-law," and often welcomed by the Chinese public for his friendliness toward China.

When he gave a lecture at Tsinghua University in Beijing in October 2014, he surprised the students by speaking Chinese throughout.

On February 7, the eve of the Chinese Lunar New Year, Zuckerberg and his wife and daughter wished the Chinese people a Happy New Year in Chinese in a video.

Many State-owned media organizations such as China Central Television and the Xinhua News Agency have Facebook and Twitter accounts to publish news catering to a foreign audience.

Global Times