The Naval Criminal Investigative Service (NCIS) launched an investigation into the death of a major general, officials said Tuesday, after the officer's body was found on the Twentynine Palms marine base in California over the weekend.

Details about the death of Maj. Gen. William Mullen have not been disclosed so far, but the retired officer was discovered dead on the base on Saturday, according to the Los Angeles Times. NCIS is a law enforcement agency for the Department of the Navy that leads criminal investigations and probes noncombat deaths of Navy sailors and Marines.

An NCIS official confirmed the agency's investigation is normal for “any non-combat, medically unattended fatalities” involving regular service members.

“Major General Mullen’s dedicated service to our nation and the Marine Corps will always be remembered,” Maj. Gen. Thomas Savage, commanding general of the Marine Air Ground Task Force Training Command, said in a statement. “Our thoughts and prayers are with his loved ones.”

Mullen previously served as the commander of the base before he retired in 2020, and served multiple tours of the Middle East. He also served as a Marine aide to former President Bill Clinton, and led a counternarcotics mission in the Los Padres National Forest, which is located in Southern and Central California.

Twentynine Palms is the largest Marine Corps base in the world, according to the base's website. It is located in the San Bernardino County in Southern California.

Coroners for the San Bernardino County Sheriff's department are conducting Mullen's autopsy, but the rest of the investigation is being conducted by NCIS, according to the sheriff department's spokesperson Mara Rodriguez.

"Out of respect for the investigative process, NCIS will not comment further while the investigation remains ongoing," NCIS spokesman Darwin Lam told Military.com.

Misty Severi is an evening news reporter for Just the News. You can follow her on X for more coverage.