SAN FRANCISCO (CBS SF/KPIX 5/AP) — The FBI believes the Chinese consulate in San Francisco is harboring a Chinese researcher who is charged in federal court in California with lying about her military background as it announced charges against that scientist and three others accused of concealing their government ties.

Tang Juan and the three other researchers are accused of lying on applications to work in the United States about their status as members of the People’s Liberation Army, which is part of the Chinese military. All are charged with visa fraud.

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Tang lied about her military affiliation in a visa application last October to work at the University of California, Davis and again during an FBI interview last month, according to a Justice Department criminal complaint.

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Agents found photographs of Tang in a uniform of the People’s Liberation Army civilian cadre and also reviewed articles from China that identified her military affiliation.

The FBI last month interviewed Tang, when she denied having served in the military or knowing the significance of the insignia on the uniform she was photographed wearing, and also found more evidence of her military affiliation when they later searched her home, the complaint says.

“The FBI assesses that, at some point following the search and interview of Tang on June 20, 2020, Tang went to the Chinese consulate in San Francisco, where the FBI assesses she has remained,” prosecutors wrote in a July 20 court filing that seeks the detention of another Chinese scientist who the Justice Department says lied about her military background to enter the U.S.

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The document alleges efforts by multiple Chinese nationals to conceal their ties to the military or government, and says “the Chinese government has instructed PLA members in the United States to obstruct justice by deleting information from their devices.”

The allegation comes amid rising tension between the U.S. and China, particularly related to theft of intellectual property — including by Chinese researchers with connections to the military and government — for Beijing’s benefit. Just this week, the U.S. ordered the closure of the Chinese consulate in Houston, and the Justice Department charged two Chinese hackers with targeting firms working on vaccines for the coronavirus.

In a statement, UC Davis said its medical school was providing law enforcement officials with information they had requested. The university said Tang had been a visiting researcher in the Department of Radiation Oncology whose work was funded by an exchange program affiliated with China’s Ministry of Education and Xijing Hosital.

Tang left the university at the end of June, and her work was based solely in the research laboratory, the school said.

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An Associated Press reporter was unable to leave a phone message with the consulate Thursday morning. No attorney for Tang was listed in court filings.

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The FBI, meanwhile, has interviewed visa holders in more than 25 American cities who are suspected of concealing their ties to the Chinese military. The Justice Department believes that the deception is part of an ongoing, government-sponsored effort to steal research and innovation from American universities for Beijing’s economic gain.

“This is another part of the Chinese Communist Party’s plan to take advantage of our open society and exploit academic institutions,” John Demers, the Justice Department’s top national security official, said in a statement.

“First, I would say the Trump administration has been on an escalating campaign of rhetoric and actions pointing to China as the enemy,” said Daniel Sneider, an international policy expert at Stanford University. “Some of this is linked, of course, to the coronavirus situation.”

The Trump administration has already closed the Chinese consulate in Houston where documents were allegedly burned. China has denounced the action as outrageous and has warned it would draw a firm response.

“As far as closing additional embassies, it’s always possible,” President Trump said earlier this week.

“Perhaps this woman and the Chinese government perceive this as a case of political persecution,” said Sneider. “I don’t know, but it is a little bit unusual.”

“But behind it is the deeper issues about economic competition, intellectual property issues between China and the United States.”

Wilson Walker contributed to this report.

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