An American scientist who has studied underground nuclear tests has been detained in China for more than 18 months on spying charges, according to his supporters and a US lawmaker.
Youlin Chen, a seismologist, has been “wrongfully detained” since November 2024, US Senator Edward Markey said in a statement Tuesday.
President Donald Trump raised Chen’s detention and asked for his freedom during a meeting with Chinese leader Xi Jinping in Beijing in May, according to Global Reach, a US non-profit that has been working with Chen’s family on his case.
Chen, who was living in Boston and has a college-age son, is the only American currently held in China designated as wrongfully detained, the non-profit said.
The case adds another point of friction between the US and China as they try to stabilize ties, and ahead of Xi’s expected visit to the US later this fall. Its revelation comes weeks after China confirmed the arrest of another US scholar, Min Zin, who it said is “suspected of spying and endangering Chinese national security.” [...]
Global Reach said there are suspicions that Chen’s detention is linked to China’s recent expansion of its nuclear capabilities, including carrying out an alleged underground nuclear test in 2020. Beijing denies this test.
China and the US have both signed, but not ratified, the Comprehensive Test Ban Treaty (CTBT) – an international agreement prohibiting “any nuclear weapon test explosion or any other nuclear explosion.”
Beijing —
An American scientist who has studied underground nuclear tests has been detained in China for more than 18 months on spying charges, according to his supporters and a US lawmaker.
Youlin Chen, a seismologist, has been “wrongfully detained” since November 2024, US Senator Edward Markey said in a statement Tuesday.
President Donald Trump raised Chen’s detention and asked for his freedom during a meeting with Chinese leader Xi Jinping in Beijing in May, according to Global Reach, a US non-profit that has been working with Chen’s family on his case.
Chen, who was living in Boston and has a college-age son, is the only American currently held in China designated as wrongfully detained, the non-profit said.
The case adds another point of friction between the US and China as they try to stabilize ties, and ahead of Xi’s expected visit to the US later this fall. Its revelation comes weeks after China confirmed the arrest of another US scholar, Min Zin, who it said is “suspected of spying and endangering Chinese national security.”
Global Reach said there are suspicions that Chen’s detention is linked to China’s recent expansion of its nuclear capabilities, including carrying out an alleged underground nuclear test in 2020. Beijing denies this test.
China and the US have both signed, but not ratified, the Comprehensive Test Ban Treaty (CTBT) – an international agreement prohibiting “any nuclear weapon test explosion or any other nuclear explosion.”
Chen’s work focuses on using seismological data to improve methods to identify and monitor nuclear tests. It has included research into North Korea’s underground nuclear testing.
Chen’s research has been funded by the US State Department and US Air Force Research Laboratory.
In December 2020, he authored a technical report that used regional seismic data recorded across Asia, including data from stations in China, to improve methods for nuclear-test monitoring and yield estimation, according to Global Reach.
A subsequent 2024 study that he authored was also funded by the US Air Force Research Laboratory and the US Department of State and “further reinforces Chen’s expertise in the seismic monitoring and detection of underground nuclear tests,” the group said.
