A former US Navy sailor has been sentenced to more than 16 years in federal prison for selling military secrets to the Chinese Communist Party. 

Jinchao Wei, 25, was convicted of trading technical secrets about the amphibious assault ship USS Essex, as well as information on the location of other Navy vessels, to a Chinese intelligence officer for $12,000. 

According to the US Department of Justice (DOJ), Wei started talking to a Chinese agent on social media in early 2022, where the foreign operative pretended to be a fan of naval ships.

However, when Wei suspected the naval enthusiast was really a spy, DOJ officials said the disgraced sailor continued speaking with them and even switched to a more secure encrypted messaging app to keep their chats hidden. 

Over 18 months, the DOJ said Wei sent thousands of pages of Navy technical manuals directly from his work computers, along with photos, videos of the USS Essex, fleet locations, and details about weapons systems on board his ship.

The stolen information included restricted details on important ship systems, such as steering controls, weapons controls, aircraft elevators, and ways US sailors handle damage or emergencies.

On Monday, Wei was sentenced in federal court to 200 months in prison.

US Attorney Adam Gordon declared: 'He betrayed his oath, his shipmates, the United States Navy, and the American people, a level of disloyalty that strikes at the heart of our national security and demanded this powerful sentence.'

After his arrest in 2023, Assistant US Attorney Fred Sheppard revealed that Wei’s mother encouraged him to betray the US when he went home to Wisconsin for Christmas.

Wei also searched online for flights to China after his handler in Beijing promised to fly him and his mother over to meet them in person, Sheppard added.

Assistant Attorney General for National Security John Eisenberg said in a statement Monday: 'Wei swore loyalty to the United States when he joined the Navy and reaffirmed that oath when he became a citizen.'

'He made a mockery of these commitments when he chose to endanger our Nation and our servicemembers by selling US military secrets to a Chinese intelligence officer for personal profit.'

The FBI and Naval Criminal Investigative Service (NCIS) discovered the spy ring after examining Wei's phone messages, audio recordings, handwritten payment receipts he sent, and other digital records that proved he contacted a real Chinese spy. 

Wei was arrested in August 2023, right as he showed up for work on the Essex. During questioning, he admitted to the FBI that he had shared 'thousands of pages' and called his own actions 'espionage.'

This past August, he was found guilty of espionage, conspiracy to commit espionage, and unlawfully exporting restricted defense information - a violation of US arms export laws.

Cyberwarfare expert James Knight of DigitalWarfare.com warned that the FBI considers China the top counterintelligence threat to the US, adding that they're focused on acquiring secrets from both the military and private sector by any means.

'The number one thing China is seeking from US spies, and broader espionage, is advanced technology and intellectual property to accelerate its own development and reduce reliance on foreign innovation,' Knight told the Daily Mail.

In terms of military tech, the expert said this includes stealing data on naval ship systems, aircraft designs, and the latest breakthroughs in semiconductors, AI, and quantum computing.

'The sale or theft of secrets benefiting China is a very common and growing concern,' Knight said.

Wei used tricks like deleting messages right away, using 'disappearing' digital drop boxes that erased themselves after 72 hours, and even received a new phone and computer from the Chinese agent to help keep the spying operation secret. 

Knight, who has three decades of cybersecurity experience, said Wei's tactics to avoid getting caught were classic examples of modern spycraft, which make it challenging for US intelligence agencies to find potential traitors selling secrets.

The expert said groups like the FBI and NCIS were 'well-equipped' to catch spy rings in the country, relying on modern tools such as device forensics and network monitoring that can flag anomalies like unusual file access or contacts.

However, Knight said 'human factors often remain the weakest link' when it comes to espionage, as Wei actually confided in another sailor that he was offered money for information on various ship locations in 2022.