US investigating whether Chinese citizen charged with flying drone over base committed 'more serious offenses'

The U.S. government is investigating whether the Chinese citizen arrested after allegedly flying a drone over Vandenberg Space Force Base in California perpetrated other offenses.

Last week, the U.S. attorney's office for the central district of California announced that 39-year-old Yinpiao Zhou, a lawful permanent resident of the U.S., was "charged with failure to register an aircraft not providing transportation and violation of national defense airspace."

But court filings indicate that "the government is continuing to investigate whether ZHOU engaged in additional, more serious offenses."

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A Chinese national flag is pictured during the medal ceremony for the women's 63kg judo event during the 2022 Asian Games in Hangzhou in China's eastern Zhejiang province on Sept. 25, 2023.  (PHILIP FONG/AFP via Getty Images)

While Zhou has not been slapped with charges of spying on behalf of China, in a sworn affidavit justifying the arrest warrant, the FBI agent heading the probe into Zhou described their own experience, noting, "I am familiar with tradecraft and techniques utilized by foreign adversarial nations and the efforts those nations undertake to collect intelligence on elements of military infrastructure of their interest."

Zhou was arrested Dec. 9 before boarding a flight to China, according to the press release about the arrest.

"This defendant allegedly flew a drone over a military base and took photos of the base's layout, which is against the law," U.S. Attorney Martin Estrada, noted.

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The Department of Justice seal is seen on a lectern ahead of a press conference announcing efforts against computer hacking and extortion at the Department of Justice in Washington, D.C. on Nov. 28, 2018. (MANDEL NGAN/AFP via Getty Images)

The release, citing an affidavit, reported that a drone was detected above the facility on Nov. 30.

"The drone systems detected that the drone flew for nearly one hour, traveled to an altitude of almost one mile above ground level, and originated from Ocean Park, a public area next to the base," the press release noted. "Base security personnel went to the park, spoke to Zhou and another person accompanying him, and learned that Zhou had a drone concealed in his jacket – the same one that flew over the base.

"Agents later searched Zhou’s drone pursuant to a federal search warrant and saw several photographs of Vandenberg Space Force Base taken from an aerial viewpoint. A search of Zhou’s cellphone showed Zhou conducted a Google search approximately one month earlier for the phrase 'Vandenberg Space Force Base Drone Rules' and messaged with another person about hacking his drone to allow it to fly higher than it could otherwise."

Nighttime sightings of unidentified aircraft in New Jersey and other parts of the country have been making national headlines, but Americans have been left wanting answers.

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Secretary of Homeland Security Alejandro Mayorkas speaks to Senior Writer at Politico Magazine Ankush Khardori during Politico's annual AI and Tech Summit on Sept. 17, 2024, in Washington, D.C. (Anna Moneymaker/Getty Images)

Department of Homeland Security Sec. Alejandro Mayorkas said during an appearance on ABC's "This Week" that some of the sightings have been drones but that others have been "manned-aircraft that are commonly mistaken for drones." He said "we know of no foreign involvement" related to "the sightings in the north-east." 

Fox News' Lee Ross contributed to this report.

Alex Nitzberg is a writer for Fox News Digital.