Charles Lieber of Harvard University is seen in this undated file photo.
CNN  — 

A Harvard University professor and two other Chinese nationals were federally indicted in three separate cases for allegedly lying to the US about their involvement with China’s government, the US attorney for the district of Massachusetts announced Tuesday.

Federal authorities told reporters the cases highlighted the “ongoing threat” posed by China using “nontraditional collectors” like academics and researchers to steal American research and technology.

Dr. Charles Lieber, 60, who is the chair of Harvard’s Chemistry and Chemical Biology Department, is accused of lying about working with several Chinese organizations, where he collected hundreds of thousands of dollars from Chinese entities, US Attorney Andrew Lelling said at a news conference.

According to court documents, Lieber’s research group at Harvard had received over $15 million in funding from the National Institutes of Health and the Department of Defense, which requires disclosing foreign financial conflicts of interests.

The complaint alleges that Lieber had lied about his affiliation with the Wuhan University of Technology (WUT) in China and a contract he had with a Chinese talent recruitment plan to attract high-level scientists to the country.

He was being paid $50,000 per month by the Chinese university and given $1.5 million to establish a nanoscience research lab at WUT, the complaint said.

CNN has reached out to an attorney for Lieber. In a statement, Harvard called the charges “extremely serious.”

“Harvard is cooperating with federal authorities, including the National Institutes of Health, and is conducting its own review of the alleged misconduct,” the university said in a statement. “Professor Lieber has been placed on indefinite administrative leave.”

In a separate indictment unsealed Tuesday, Yanqing Ye, a 29-year-old Chinese national, was charged with visa fraud, making false statements, conspiracy and being an unregistered agent, the US attorney’s office said.

Yanqing had falsely identified herself as a “student” on her visa application and lied about her military service while she was employed as a scientific researcher at Boston University, according to the indictment. She admitted to federal officers during an April 2019 interview that she held the rank of lieutenant with the People’s Liberation Army, court documents show.

Yanqing is accused of accessing US military websites and sending US documents and information to China, according to documents.

Last week, a cancer researcher, Zaosong Zheng, was indicted for trying to smuggle 21 vials of biological material out of the US to China and lying about it to federal investigators, Lelling said.

Zaosong, 30, whose entry was sponsored by Harvard University, had hidden the vials in a sock before boarding the plane, according to Lelling.

“This is not an accident or a coincidence. This is a small sample of China’s ongoing campaign to siphon off American technology and know-how for Chinese gain,” Lelling said.

Lelling said Boston is a target for this “kind of exploitation” because of its universities, hospitals, research institutions and tech companies in the area.

Lieber is scheduled to appear later Tuesday afternoon in federal court in Boston. Yanqing is currently in China.

Zaosong was arrested and charged last month. He has been detained since December 30.

CNN has reached out to an attorney Zaosong. It was not immediately clear if Yanqing had a lawyer.

CNN’s Bre’Anna Gran contributed to this report.