A Chinese national from Wuhan, Chengxuan Han, was arrested at Detroit Metropolitan Airport while attempting to smuggle biological materials into a University of Michigan lab. U.S. officials found she had sent four packages containing concealed roundworm specimens in 2024–25. Initially claiming they were plastic cups, Han admitted under FBI and Homeland Security questioning that the contents related to her Ph.D. work at Huazhong University of Science and Technology.
Han is the third Chinese scientist linked to smuggling biological materials into Michigan this month. Earlier arrests include two University of Michigan–connected researchers who allegedly attempted to bring in Fusarium graminearum, a known crop pathogen classified as a “potential agroterrorism weapon”.
Federal authorities expressed national security concerns. FBI Detroit’s Special Agent in Charge stated these incidents threaten public safety and undermine trust in American research. U.S. Customs and Border Protection noted Han deleted data from her device before traveling and had been denied U.S. visas twice in March—her failure to answer basic questions reportedly raised additional red flags.
The smuggling ring highlights growing scrutiny of Chinese nationals in U.S. research institutions amid concerns over biological espionage. Michigan prosecutors and the FBI have launched coordinated investigations, signaling broader federal enforcement. Han remains in custody pending a bond hearing, and two prior suspects arrested for agroterrorism-related offenses are also awaiting trial.
