Jerry Chung Shing Lee, a naturalized US citizen, and former Cia Officer was arrested on Monday and charged with being in unlawful possession of national defense information. Lee is also suspected of a more serious crime of spying for the Chinese government according to NBC News reports.

According to Federal authorities, Lee was arrested after landing in the US from his home in Hong Kong where he currently resides. The unlawful possession of classified information charge emanates from a 2012 investigation where Lee was found with two notebooks containing the true identities of CIA assets and covert facilities in China.

CIA assets and covert facilities are the most highly guarded [VIDEO] secrets of the Intelligence Agency.

No espionage charges

Despite the fact that Lee is suspected of a more serious crime of espionage, which carries the death penalty, authorities preferred a lesser charge of unlawful possession of classified information.

According to NBC News sources familiar with the case, the reason for the reduced charge could be due to the fact that the US government does not have enough evidence to carry an espionage charge, or is avoiding spilling of classified and sensitive information in open court.

The FBI task force that investigated Lee's case in 2012, went to great lengths which included searching his hotel room and finding two notebooks, of 21 pages each, which contained operational phone numbers, names of assets, meeting locations and covert facilities, according to a filed court affidavit.

CIA operations compromised

The CIA believes the classified information [VIDEO] was given to the Chinese government by Lee, leading to arrests and deaths of several active CIA agents stationed in China in 2010.

At the time, the CIA watched in disbelief as some of its best agents were either jailed or executed in China, mystified by the source of the leakage.

Some investigators at the time believed China had hacked into the CIA database and accessed the information. But it was only a matter of time before 53-year-old Lee became the focus of the investigation.

According to NBC News sources, it was one of the worst intelligence breaches since two former CIA and FBI agents leaked classified information to the Russian government in the 90's. The leaked information also led to the deaths of several US agents active in Russia at the time.

The two US agents responsible for the act of espionage, Aldrich Ames, and Robert Hansen, are currently serving life sentences in jail.