On June 5, famous astrophysicist Fang Lizhi and his wife Li Shuxian met with Perry Link, Link, who was at the time director of the Beijing office of the National Academy of Science’s Committee on Scholarly Communication with the People’s Republic of China. Accompanied by Link, Fang and Li went to seek asylum at the US Embassy in Beijing. There, they were cared for by Raymond F. Burghardt, who was at the time chargé d'affaires of the embassy.

Since the beginning of the 1989 student movement, Fang Lizhi and Li Shuxian had been regarded by the authorities as the masterminds behind the scenes. Fang Lizhi wrote in his autobiography, "As early as the third day after the student petition, on April 20, the Beijing authorities began to communicate internally that the student movement in Beijing had been 'created and directed by Fang Lizhi and his wife'. With that as their excuse, they were waiting for an opportunity to kill the movement."

On the day of the June 4th crackdown, Link visited Fang and Li at their home and took them to the US embassy in Beijing. At first, Burghardt explained that the two of them couldn't be kept a secret. Eventually, with the assistance of the US State Department's Jeffrey Bader, the embassy re-accommodated the two as "guests of President George Bush". Fang and Li eventually took refuge for a year in the clinic within the US ambassador's residence.

Also on that same day, news that Fang and Li sought asylum in the US embassy reached the Central Committee. Li Peng wrote in his diary, "Peking University professors, liberals, and commanders of the turmoil, Fang Lizhi and Li Shuxian, have fled to the US embassy, requesting protection. Their true faces as foreign slaves have been exposed." A Xinhua News Agency report stated, "Fang Lizhi has often in recent years used American and other foreign media to make speeches attacking the socialist system, and abusing the party and the government. Regarding Fang's status, the Americans are clearly aware. In the current circumstances, for the US embassy in China to provide asylum to people like Fang Lizhi, this is interference in China's internal affairs."

On June 12, the Ministry of Public Security issued a wanted notice for Fang Lizhi and Li Shuxian. More than a year later, on June 25, 1990, they took a US Air Force plane to the United Kingdom. They finally arrived in the US six months later. Later on, Fang Lizhi went to teach at the Department of Physics at the University of Arizona in the US.

References: Zhang Wanshu, "The Big Bang of History: A Complete Record of the June 4th Incident"; "The Critical Moment – Li Peng Diaries"; "The Tiananmen Papers"; [紐約時報中文網("New York Times Chinese Edition")(Chinese)] (https://cn.nytimes.com/china/20160329/cc29fanglizhi/zh-hant/) "Vision Times" (1)(https://www.secretchina.com/news/b5/2012/04/08/447230.html), (2) (https://www.secretchina.com/news/gb/2016/01/01/447432.html); (https://zh.wikipedia.org/wiki/方励之) [大公報("Ta Kung Pao")(Chinese)] (https://drive.google.com/file/d/1_cBBqw_njMz6yuSfb6RsklvfEcRwpR8Z/view?usp=sharing); [文匯報("Wen Wei Po")(Chinese)] (https://drive.google.com/file/d/1z8RH3U_mGIFv_z93QJs2uzlU-SN-aH_-/view?usp=sharing); [快報("Express")(Chinese)] (https://drive.google.com/file/d/10rv0ZpZpQjQUaqOit9KaH4F83aE5MrB4/view?usp=sharing); [東方日報("Oriental Daily News")(Chinese)] (https://drive.google.com/file/d/1vNo1tjPeAzw2e_1bHYKZ5G1mFM-Jfjm3/view?usp=sharing)