Trump urges Xi to release detained American scientist Youlin Chen

During a May 2026 state visit to Beijing, Donald Trump pressed Xi Jinping to release detained Chinese-born American seismologist Youlin Chen.

Chen, a Boston academic who became a U.S. citizen in 2011, was arrested on November 5, 2024, at Beijing Capital International Airport as he prepared to fly home after visiting family.

Chen has been held in China without trial and faces espionage charges over research that examined how to detect North Korean nuclear tests. That work was carried out on U.S. government-funded projects and placed Chen at the junction of science, arms control and the wider strategic rivalry between Washington and Beijing.

Marco Rubio designated Chen as wrongfully detained in March 2026, making him the only American held in China with that designation. Chen has diabetes, high blood pressure and high cholesterol, while his wife, Yufang Rong, said she has not been able to speak with him for more than 600 days. Chen has not spoken directly with his family since the arrest.

Sen. Edward J. Markey of Massachusetts said Chen has been in pre-trial detention since his arrest, went 434 days without access to his lawyer and has never been convicted of a crime. Markey has urged Rubio to make Chen’s case a wrongful-detention priority and has raised it personally with Chinese Ambassador Xie Feng.

China’s foreign ministry rejected the U.S. characterization. There is no such thing as wrongful detention in China, and judicial organs handle cases according to law. The White House has not publicly announced the case, but Rong said officials told her Trump raised Chen’s detention with Xi during the Beijing visit and that Xi promised to look into it.

Chen is among at least 12 Americans the Foley Foundation counts as unjustly held in China, including some under exit bans.