A California man with ties to China has been arrested in connection with a plot to steal blueprints of nuclear missile launch sensors developed for the United States government, the Justice Department announced Wednesday.

The files allegedly stolen by Chenguang Gong included trade secrets on technology used to detect nuclear missile launches and track ballistic and hypersonic missiles, which would be “dangerous to U.S. national security if obtained by international actors,” court documents obtained by USA TODAY said. 

Two of three storage devices Gong allegedly transferred files onto still haven’t been found, Federal Bureau of Investigation agent Igor Neyman said in an affidavit filed in U.S. District Court for the Central District of California.

U.S. attorney Martin Estrada said Gong previously attempted to provide China with information to aid its military.

“We know that foreign actors, including the PRC (People’s Republic of China), are actively seeking to steal our technology, but we will remain vigilant against this threat by safeguarding the innovations of American businesses and researchers,” Estrada said.

Gong, 57, of San Jose, was charged Tuesday with theft of trade secrets, which carries a maximum penalty of 10 years in federal prison.

FBI: Two hard drives with trade secrets still not found

In January 2023, Gong began working at a company based in Malibu, California that develops technology used to detect nuclear missile launches and track ballistic and hypersonic missiles for the Department of Defense and other U.S. government contractors, Neyman said in his affidavit.

Between March and April 2023, Gong allegedly transferred more than 3,600 files from his work laptop to three personal storage devices, including files with trade secrets on technology for the military.

“These files describe the methods, designs, techniques, processes, specifications, testing, and manufacture of these technologies and would be extremely damaging economically if obtained by the Victim Company’s competitors, and would be dangerous to U.S. national security if obtained by international actors,” Neyman said.

In early April, as Gong continued transferring classified files, he accepted a job at a competitor company, Neyman said. Later that month, the company he was stealing files from terminated his employment after finding a flash drive, one of three storage devices Gong allegedly used to illicitly transfer files, according to the affidavit. 

Seven days after starting a job at the competitor company, the FBI executed a search warrant at Gong's temporary residence in Thousand Oaks, California, where agents found the company’s files on some of his devices, Neyman said. But the two hard drives Gong allegedly transferred trade secrets on still have not been located, according to the affidavit, and Gong has denied knowing of the two devices, though he admitted to transferring some files to the flash drive previously found.

Man employed by defense contractor, indictment says

From 2014 to 2022, Gong allegedly submitted several applications to “talent programs” administered by the Chinese government, according to the affidavit. Neyman said China has established talent programs to find people outside of China who have special skills and knowledge that could boost the country’s economy, including its military.

During the same period, Neyman said Gong was employed by several major technology companies in the U.S. and one of the world’s largest defense contractors. In applications to China's programs, Gong allegedly proposed projects that mirrored his work for U.S. companies and said they would be useful to China’s military.

“The theft of trade secrets, especially of sensitive military technology, undermines our national security, erodes U.S. competitiveness in the global market, and harms the businesses and individuals who have invested time, resources, and creativity into developing innovative technologies,” said Donald Alway, assistant director in charge of the FBI Los Angeles field office.

"Our actions today send a strong message that anyone willing to steal proprietary information from U.S. businesses will face consequences in the criminal justice system," Alway said.