A petitioner with her grievances written on her clothes walks along a street in Beijing Tuesday, December 22, 2015. After months behind bars, Pu Zhiqiang, one of China's most prominent human rights lawyers, left a detention center Tuesday after receiving a suspended prison sentence in a case involving online comments critical of the ruling Communist Party. (Photo by Ng Han Guan/AP Photo)

A migrant worker wearing face masks to help curb the spread of the coronavirus walks up to a pedestrian bridge in Beijing, Sunday, December 6, 2020. Provincial governments across China are placing orders for experimental, domestically made coronavirus vaccines, though health officials have yet to say how well they work or how they may reach the country's 1.4 billion people. (Photo by Andy Wong/AP Photo)

American Ballet Theater's dancers are silhouetted as they rehearse for the opening night at the Shanghai Grand Theater in Shanghai, Thursday, November 2, 2023. The American national ballet company is returning to China for the first time in a decade for shows in Shanghai and Beijing in the latest sign strained relations between the United States and China are beginning to thaw. (Photo by Ng Han Guan/AP Photo)

A delegate poses for a photo at the end of the closing ceremony of the 20th National Congress of the Chinese Communist Party in front of the Great Hall of the People in Beijing, China, on Saturday, October 22, 2022. President Xi Jinping is officially set for a third term surrounded by allies, after key Communist Party officials without close ties to the Chinese leader exited the nation's top leadership body. (Photo by Bloomberg)

Chinese artist Kong Ning poses in a costume symbolizing a butterfly, which is decorated with 365 masks on its wings to represent the number of days in a year, during her performance art at the Badaling section of the Great Wall on the outskirts of Beijing January 1, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance art “Hua Die” (transforming into a butterfly) and performed it on the first day of the new year as she hopes that China has clean air for this year. (Photo by Kim Kyung-Hoon/Reuters)

Cheng Liping, whose husband Ju was onboard Malaysia Airlines Flight MH370 which disappeared on March 8, 2014, shows a picture of she and her husband together and an old card with a message given by her husband, at a park near her house where she and her husband used to visit during an interview with Reuters in Beijing July 24, 2014. Cheng said her life has been totally changed since the incident. Their two little sons, who don't know about this incident, keep asking her when their dad is coming back. Six months after Malaysia Airlines Flight MH370, with 239 mostly Chinese people on board, disappeared about an hour into a routine journey from Kuala Lumpur to Beijing March 8, loved ones of missing passengers derive what comfort they can from what's left behind after the world's greatest aviation mystery. More than two dozen countries have been involved in the air, sea and underwater search for the Boeing 777 but months of sorties failed to turn up any trace – even after narrowing the search area to the southern Indian Ocean – long after batteries on the black box voice and data recorders had gone flat. (Photo by Kim Kyung-Hoon/Reuters)

Visitors look out from a balcony in a quiet mall area with closed retail shops and restaurants only offering takeaway on Tuesday, May 10, 2022, in Beijing. China's capital began another round of three days of mass testing for millions of its residents Tuesday in a bid to prevent an outbreak from growing to Shanghai proportions. (Photo by Ng Han Guan/AP Photo)