SACRAMENTO, Calif. (AP) — A Chinese scientist charged with visa fraud after authorities said she concealed her military ties to China in order to work in the U.S. made her first appearance Monday in federal court by video.

Juan Tang, 37, was appointed a federal public defender and U.S. Magistrate Judge Deborah Barnes ordered Tang to remain in custody, saying she is a flight risk, while her attorney prepares an argument to allow her release on bail.

READ MORE: Boy, 8, Hailed A Hero After Discovering Baby Sister Unresponsive In Pool

The Justice Department last week announced charges against Tang and three other scientists living in the U.S., saying they lied about their status as members of China’s People’s Liberation Army. All were charged with visa fraud.

Prosecutors said Tang lied about her military ties in a visa application last October as she prepared to work at the University of California, Davis and again during an FBI interview in June. Agents found photos of Tang dressed in military uniform and reviewed articles in China identifying her military affiliation, prosecutors said.

READ MORE: Man Apologizes After Video Shows Street Vendor Attacked

The federal public defender’s office in Sacramento did not respond immediately to an email request for comment.

Prosecutors said Tang sought refuge at the Chinese consulate in San Francisco after speaking with agents in June. U.S. marshals arrested her Friday and booked her into Sacramento County Jail, where she remains.

The University of California, Davis said Tang left her job in June as a visiting researcher in the Department of Radiation Oncology.

MORE NEWS: Folsom Shuts Sutter Street Down To Open Businesses

The arrests come as tensions rise between China and the U.S.