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Two dozen U.S. Marines have been discharged and at least one has been sentenced to time in prison following an investigation into their involvement in human smuggling and drug-related issues, a spokesperson for the Marines told

The Marines, all from California's 1st Marine Division, faced varying levels of punishment from administrative to judicial action, the spokesperson told

One Marine has been sentenced to 18 months in a military prison, and one other currently awaits a general court-martial trial, the most serious type of military trial, reported. Nine Marines who faced a courts-martial trial pleaded guilty to the charges and were discharged.

None of the 24 members dismissed were honorably discharged, and at least two of them were discharged with bad-conduct discharges, a spokesperson for the Marines told

The investigation into the battalion members began last year when border patrol agents arrested Lance Cpls. Byron Darnell Law II and David Javier Salazar-Quintero about seven miles from the US/Mexico border, according to the report. The officers determined that the Marines were transporting three undocumented immigrants.

The initial arrests reportedly led officers to learn of the other various drug-related and human trafficking crimes the 24 Marines would eventually be accused of, according to the report.

Police also arrested Francisco Saul Rojas-Hernandez after several of the Marines told authorities the man, who was arrested in San Diego, California, had orchestrated the human smuggling and paid the Marines to traffick the humans into the US.

According to a report from the San Diego Union-Tribune on February 5, federal prosecutors filed conspiracy charges against Rojas-Hernandez, claiming he conspired to recruit members of the Marines and other US citizens to transport people who had just unlawfully crossed the US/Medico border around San Diego.

Per the Union-Tribune, seven other US citizens who were arrested for transporting people who had illegally entered the country had named “Rojas” as the person who had organized the operation.

As had previously reported, prosecutors had dropped most of the drug and human trafficking charges against the two-dozen Marines who have since been discharged days after a military court ruled that their arrest outside of their Camp Pendleton, which the San Diego Union-Tribune said occured in front of their 800-person battalion, was unlawful. The majority of those accused and discharged faced administrative action outside the Military court system.

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