The federal government has arrested a naturalized American citizen who served in the Army and as a CIA officer for unlawfully possessing classified information that “could cause exceptionally grave damage” to America’s national security, announced the U.S. Department of Justice (DOJ).

Citing unnamed sources familiar with the case, NBC News reported that American authorities suspect the defendant shared “top secret information” with Beijing, potentially resulting in the death or imprisonment of about 20 U.S. agents in China.

Citing court documents that highlight a 2012 FBI search of the defendant’s belongings, DOJ announced that the federal government found the accused spy, identified as 53-year-old Jerry Chun Shing Lee (aka Zhen Cheng LiLee), “was in unauthorized possession of materials relating to the national defense.”

The court documents revealed:

A review of photographs taken during the August 13, 2012, search in Hawaii and the August 15, 2012, search in Virginia revealed that, during his stay in both hotels, LEE possessed two small books (the “books”) best described as a datebook and an address book.

…

The datebook contained handwritten information pertaining to, but not limited to, operational notes from asset meetings, operational meeting locations, operational phone numbers, true names of assets, and covert facilities … The address book contained true names and phone numbers of assets and covert CIA employees, as well as the addresses of CIA facilities.

According to the affidavit, the CIA determined that the books contained classified data, including “Top Secret information, the disclosure of which could cause exceptionally grave damage to the National Security of the United States.”

NBC News learned that U.S. President Donald Trump’s administration suspects Lee was spying on behalf of China.

“Sources familiar with the case say he is suspected of funneling information to China that caused the deaths or imprisonment of approximately 20 American agents, in one of the worst intelligence breaches in decades,” reported the news outlet.

Last year, the New York Times (NYT) revealed that, beginning in 2010, the communist Chinese government demolished CIA spying operations across the country, murdering or jailing “more than a dozen sources over two years and crippling intelligence gathering there for years afterward.”

Perplexed by the cause behind Beijing’s actions, current and former U.S. officials reportedly described the CIA breach “as one of the worst in decades.”

Some American officials did suspect at the time that a double agent had betrayed the United States, a possibility that may be closer to reality than previously thought.

Federal agents detained the ex-CIA officer suspected of spying for China on Monday night as he arrived at the John F. Kennedy International Airport in New York from Hong Kong, China.

Court documents showed “Lee began working for the CIA as a case officer in 1994, maintained a Top Secret clearance and signed numerous non-disclosure agreements during his tenure at CIA,” noted DOJ.

In August 2012, the FBI carried out court-authorized searches of Lee’s room and luggage in Hawaii and Virginia while the suspected mole was traveling back to the United States from Hong Kong.

That is when federal officers “found that Lee was in unauthorized possession of materials relating to the national defense,” revealed DOJ.

“He is charged with unlawful retention of national defense information and faces a maximum penalty of 10 years in prison, if convicted,” noted the department.

Citing anonymous sources, NBC News reported that the Trump administration might not charge Lee with espionage, which carries the death penalty, despite the fatal consequences of his actions.

“It may be that the government doesn’t have the proof required for such a charge, or that it doesn’t want to air secrets in an open courtroom,” explained NBC News. “But sources say Lee was the subject of an intense — and extremely secret — counterintelligence investigation.”

Court documents revealed that the accused spy served in the U.S. Army from 1982-1986. He graduated from Hawaii Pacific University in 1992 with a bachelor’s degree in International Business Management and received a master’s degree in Human Resource Management in 1993.