Two U.S. Navy sailors have been arrested on charges related to national security and tied to China, U.S. officials said Thursday.

Jinchao Wei, a 22-year-old sailor assigned to the San Diego-based USS Essex, was arrested Wednesday on a charge related to espionage involving conspiracy to send national defense information to Chinese officials, according to the U.S. officials.

Federal officials released an indictment against Wei on Thursday and provided more details at a news conference in San Diego.

In an indictment released Thursday, federal prosecutors allege that Wei made contact with a Chinese government intelligence officer in February 2022, and at the officer’s request, provided photographs and videos of the ship he served on. The information he disclosed included technical and mechanical manuals as well as details about the number and training of Marines during an upcoming exercise, the Justice Department said.

The Justice Department charged Wei under a rarely-used Espionage Act statute that makes it a crime to gather or deliver information to aid a foreign government.

During the course of the relationship, the unnamed Chinese intelligence officer instructed Wei not to discuss their relationship, to share non-public information with the agent, and to destroy evidence to help them cover their tracks, officials said.

The USS Essex is an amphibious assault ship known as a Landing Helicopter Dock that has a full flight deck and can carry an array of helicopters, including the MV-22 Ospreys.

The Justice Department separately announced charges against a second Navy service member, accusing Wenheng Zhao of collecting bribes in exchange for giving sensitive U.S. military photos and videos to a Chinese intelligence officer between August 2021 through at least this May. The information included operational plans for a U.S. military exercise in the Indo-Pacific Region. Prosecutors say Zhao also surreptitiously recorded information that he handed over.

The two sailors were charged with similar crimes, but they were charged as separate cases and it wasn’t clear Thursday if the two were courted or paid by the same Chinese intelligence officer.