Yunqing Jian has been charged with conspiring to introduce a toxic fungus, Fusarium graminearum, into the United States, following her arrest on June 2, 2025, after previously tending to the fungus in a lab.

Chengxuan Han, a Chinese national, faces accusations of attempting to smuggle biological materials related to roundworms into the U.S. for a University of Michigan laboratory.

The FBI has stated that the intercepted materials do not appear to pose a significant danger, according to expert assessments.

Prosecutors are concerned that both Jian and Han may attempt to flee the country if released, which has led to their continued detention pending further legal proceedings.

U.S. Attorney Jerome Gorgon, Jr. emphasized the seriousness of these cases, highlighting potential threats to national security and the misuse of taxpayer funds.

Legal expert Vonda Evans noted the evolving nature of security threats in research, particularly regarding agroterrorism, and commended enforcement efforts that have intercepted these materials.

Both researchers are alleged to have violated regulations requiring permits for transporting foreign biological materials across borders.

Federal authorities have not accused the scientists of intending to release the fungus into the environment, and the University of Michigan has stated it has not engaged in any wrongdoing.

During a court appearance on June 13, 2025, Jian, who initially resisted indefinite detention, ultimately consented to remain in custody after discussions with her legal counsel.

Chengxuan Han's preliminary hearing is set for June 30, 2025, while the date for Yunqing Jian's preliminary hearing is still pending.

The incidents underscore the broader scrutiny of biological smuggling, particularly involving Chinese nationals, amid heightened concerns over espionage and agricultural security.

Investigators revealed that Han initially misrepresented the contents of her packages, which included biological samples, and had wiped her electronic devices before traveling to the U.S.