A federal judge in San Diego sentenced Jinchao Wei, 25, to 200 months after he was convicted in August of six crimes, including espionage.

Jinchao Wei was an engineer for the amphibious assault ship USS Essex, pictured above in 2018.Cpl. A. J. Van Fredenberg / U.S. Marine Corps

A former U.S. Navy sailor convicted of selling technical and operating manuals for ships and operating systems to an intelligence officer working for China was sentenced Monday to more than 16 years in prison, prosecutors said.

A federal judge in San Diego sentenced Jinchao Wei, 25, to 200 months. A federal jury convicted Wei in August of six crimes, including espionage. He was paid more than $12,000 for the information he sold, the U.S. Department of Justice said in a statement.

Wei, an engineer for the amphibious assault ship USS Essex, was one of two California-based sailors charged on Aug. 3, 2023, with providing sensitive military information to China. The other, Wenheng Zhao, was sentenced to more than two years in 2024 after he pleaded guilty to one count of conspiracy and one count of receiving a bribe in violation of his official duties.

U.S. officials have for years expressed concern about the espionage threat they say the Chinese government poses, bringing criminal cases in recent years against Beijing intelligence operatives who have stolen sensitive government and commercial information, including through illegal hacking.

Wei was recruited via social media in 2022 by an intelligence officer who portrayed himself as a naval enthusiast working for the state-owned China Shipbuilding Industry Corporation, prosecutors said.

Evidence presented in court showed Wei told a friend that the person was "extremely suspicious" and that it was "quite obviously" espionage. Wei disregarded the friend`s advice to delete the contact and instead moved conversations with the intelligence officer to a different encrypted messaging app Wei believed was more secure, prosecutors said.

Over the course of 18 months, Wei sent the officer photos and videos of the Essex, advised him of the location of various Navy ships and told him about the Essex`s defensive weapons, prosecutors said.

Wei sold the intelligence officer 60 technical and operating manuals, including those for weapons control, aircraft and deck elevators. The manuals contained export control warnings and detailed the operations of multiple systems aboard the Essex and similar ships.

He was a petty officer second class, which is an enlisted sailor`s rank.

The Navy`s website says the Essex is equipped to transport and support a Marine Corps landing force of over 2,000 troops during an air and amphibious assault.

In a letter to the judge before sentencing, Wei apologized and said he shouldn`t have shared anything with the person, whom he had considered a friend. Wei said "introversion and loneliness" clouded his judgment.