A Chinese doctoral student has been arrested for allegedly smuggling biological specimens into the United States for use in research at the University of Michigan, marking the latest development in an expanding federal investigation into biosecurity threats and foreign interference in American academic institutions.
The suspect, Chengxuan Han, is currently enrolled in a PhD program at the College of Life Science and Technology at Huazhong University of Science and Technology in Wuhan, China. According to the U.S. Attorney’s Office for the Eastern District of Michigan, Han is facing federal charges for smuggling and providing false information to border officials.
Authorities allege that Han mailed four separate parcels from China to individuals affiliated with a University of Michigan laboratory between 2024 and 2025. These packages, which contained undeclared biological substances—specifically roundworms—were reportedly concealed in a manner intended to bypass customs inspection.
Upon her arrival at Detroit Metropolitan Airport on June 8, 2025, using a J-1 exchange visitor visa, Han was subjected to a routine screening. During questioning, she allegedly denied having sent any materials or possessing knowledge of the packages’ contents. However, a search of her electronic devices, which had been wiped just days earlier, raised suspicions.
Following further questioning by the FBI, Han admitted to mailing the biological specimens and acknowledged that she had lied to U.S. Customs and Border Protection officers during the inspection.
Han is set to appear before a federal judge in Detroit later today.
“This alleged act of smuggling by a researcher from a Wuhan-based university into one of our public research institutions reflects a disturbing trend,” said U.S. Attorney Jerome F. Gorgon, Jr. “We cannot allow taxpayer-funded institutions to be exploited for unauthorized or covert scientific activity tied to foreign governments.”
The FBI, CBP, and Homeland Security Investigations (HSI) are collaborating on the case, which officials say is part of a broader probe into the illegal importation of biological agents that may pose a risk to national security and agriculture.
This latest incident echoes an earlier case involving two Chinese nationals, Zunyong Liu and Yunqing Jian, who were charged in 2024 with smuggling Fusarium graminearum, a fungus known to damage cereal crops and produce harmful toxins. The fungus is considered a potential agricultural bioterrorism agent due to its capacity to destroy grain harvests and contaminate food supplies.
Investigators discovered that Liu had transported the fungus into the U.S. during a visit to Jian, who worked at the same University of Michigan lab. Electronic evidence confirmed the two were collaborating on unauthorized research involving the pathogen. Jian was also found to have received research funding from the Chinese government and had documented ties to the Chinese Communist Party.
“The activities uncovered in this investigation represent a credible threat to public safety and the integrity of our research institutions,” said Cheyvoryea Gibson, Special Agent in Charge of the FBI’s Detroit Field Office.
As the federal inquiry deepens, U.S. officials remain vigilant against biological threats and foreign-sponsored efforts to compromise American scientific infrastructure and national food security.