US Nuclear Test Expert Detained In China For More Than 18 Months Over Espionage Allegations

US Nuclear Test Expert Detained in China for More Than 18 Months Over Espionage Allegations An American scientist who researched methods for detecting underground nuclear tests has been detained in China for more than 18 months, according to his supporters, his family and a US lawmaker, in a case that has added fresh tension to already strained US-China relations. The scientist, Youlin Chen, a Chinese-born US citizen and seismologist, was arrested in November 2024 while visiting China and has since faced espionage-related allegations. His supporters and US officials say he has been “wrongfully detained” and are calling for his release.

Chen’s research focused on using seismic data to distinguish natural earthquakes from underground explosions, including nuclear tests. His work included US-funded studies examining ways to detect nuclear activities, particularly in relation to North Korea’s nuclear program. US Senator Edward Markey has described Chen’s detention as wrongful, while advocacy groups working with his family have urged Washington to continue diplomatic efforts to secure his freedom. According to Chen’s family and supporters, he has spent months in detention without a resolution to his case. They say his scientific work relied on publicly available information and did not involve classified material. The Chinese government has rejected claims that Chen was being held unlawfully, saying that authorities are handling the case according to Chinese law. The case has become another point of friction between Washington and Beijing, with concerns over the treatment of scientists, national security issues and the risks faced by researchers working in sensitive field.