A visiting researcher at UCLA has been arrested and charged with destroying evidence, the latest Chinese national to face accusations in U.S. courts of trying to conceal ties to China’s military or government institutions.

The FBI began investigating Guan Lei in July, suspecting he had committed visa fraud and possibly transferred “sensitive software or technical data” from UCLA, where he studied machine-learning algorithms in the school’s mathematics department, to “high-ranking” officials in the Chinese military, an FBI agent wrote in an affidavit.

Guan, 29, isn’t charged with those crimes. Instead he’s accused of destroying evidence after agents, staking out his apartment in Irvine, saw him pull a computer hard drive from his sock and throw it into a trash bin, Agent Timothy D. Hurt wrote in the affidavit.

Guan discarded the damaged drive days after being interviewed by investigators and attempting to board a flight back to China, Hurt wrote.

Guan made an initial appearance in court Friday, a spokesman for the U.S. attorney’s office in Los Angeles said. It couldn’t be determined if he had a lawyer who could speak on his behalf. A spokesman for UCLA said the school “cooperated fully” with investigators.

Guan is the latest Chinese national studying at a U.S. university to be charged with a federal crime. In California alone, visiting scientists at three of the state’s top research institutions — Stanford, UC San Francisco and UC Davis — have been arrested and detained.

Federal prosecutors have said in court papers and during detention hearings that they and the FBI have uncovered a campaign by Chinese officials to seed U.S. universities with clandestine military scientists.

Guan previously attended the National University of Defense Technology in China, one of three universities overseen by the country’s military, Hurt wrote in the affidavit. Guan told agents that as a student, he occasionally wore a uniform on state holidays and underwent some military training that involved “a lot of walking, running and standing,” the affidavit said, but he insisted that he was just a “normal student” and not a military officer.

Since the arrest in June of UC San Francisco researcher Xin Wang, Chinese authorities have told alleged military officers studying at U.S. colleges to destroy evidence and coordinated attempts to spirit them out of the country, one prosecutor wrote in a court filing. U.S. authorities say that, unknown to State Department officials who granted him a visa, Wang holds a rank in the Chinese military that corresponds to a major in the U.S. armed forces.

FBI agents had, in fact, asked Guan whether he had discussed Wang’s arrest with anyone at a Chinese consulate.

“Isn’t he a soldier?” Guan told the agents, according to the affidavit. “I am not in the same category as him. Plus, the internet says Wang was stealing information. I am here openly, you can search my stuff.”

Guan conducted research at UCLA since 2018, working with a professor — unnamed in court documents — to develop “an optimization algorithm” and apply it to machine learning, the affidavit said.

Hurt wrote that Guan had access at UCLA to a “graphics processing unit,” a piece of technology with potential military applications, but the professor told agents “he was not alarmed by Guan’s activities and could not think of military or proprietary applications Guan might have unlawfully accessed at UCLA.”

Guan told the FBI the professor left UCLA in 2019 to work for an unidentified “Chinese multinational technology company,” the affidavit said.