A female and her boyfriend in Michigan have been accused of smuggling biological pathogens “possibly causing devastating diseases in crops” to the United States, according to federal charge documents.

Yunqing Jian, 33, is a postdoctoral fellow at the University of Michigan, and her boyfriend Zunyong Liu, 34, is charged with multiple counts, including a conspiracy to deceive the United States, smuggle goods into the country, and make false statements to investigators, the complaint said.

The complaint said Liu entered the country at the Detroit Metropolitan Airport in July when border officers discovered a pathogen in his backpack, a fungus known as Fushari. A small clump of red plant material was found in four plastic bags.

The complaint says that Liu and his girlfriend studied pathogens as college students in China. Since 2023, Jian has been working in the University of Michigan’s Molecular Plant-MicroLeaf Interactive Laboratory.

Liu initially told the officer that he didn't know what the materials were, and that someone must have planted them in his schoolbag, but then he told a different story.

"Liu said he deliberately hid the samples in his backpack because he knew there were restrictions on the import of the materials," the complaint said. "Liu confirmed that he intentionally placed the samples in a ball of tissue, so it is unlikely that CBP officials' findings would be found and confiscated, and that he could continue research in the United States."

According to the complaint, Liu also said he plans to use the University of Michigan lab to conduct research on pathogens. The complaint said that when investigators spoke to Jiang, she denied any knowledge about Liu's smuggling or planning to study pathogens.

However, a check on Liu's electronic devices was found and a 2022 WeChat message was found, in which they discussed smuggling seeds to the United States.

"I put them on Martin's boots," the complaint said. "In a small bag. Zipper bag. Very small."

"Good," the complaint said. "Just keep it in your shoes."

During a federal court hearing Tuesday afternoon, a judge ordered Jian to remain in jail after prosecutors described her flight risk. Liu was allowed to enter the country after the pathogen was allegedly found in his backpack.

The FBI Counter-Intelligence Department conducted an investigation.

"Photographic cereal elements cause billions of dollars in economic losses worldwide every year," the complaint said. "The toxins produced by fusarium graminearum cause vomiting, liver damage and reproductive defects in livestock and humans."

"The so-called actions of these Chinese nationals - including loyal members of the Chinese Communist Party - are the most serious national security concerns," U.S. Attorney Jerome Gorgon said in a statement.

The Chinese embassy in Washington did not immediately respond to a request for comment.

The University of Michigan said it condemns “any action attempting to cause harm, threaten national security or undermine the university’s critical public mission.”

"It is important to note that the university has not received funding from the Chinese government from the research conducted by the defendants," the university added in a statement. "We have and will continue to work with federal law enforcement in its ongoing investigations and prosecutions."