Mexican Navy attack in Sinaloa leads to operation killing 10 armed civilians and detaining three suspects

On July 4‑6 2026, members of the Mexican Navy (Secretaría de Marina) were ambushed with improvised explosive devices in the community of San Marcos, Mazatlán, Sinaloa. The attack wounded three sailors and killed one, identified as Marine Cristian Eduardo, who died while receiving medical care.

In response, the Secretariat of Security and Protection Citizens (SSPC) launched a coordinated operation in the neighboring municipality of El Rosario. Federal forces – Navy, Army and security units – engaged armed civilians, resulting in the deaths of ten (authorities later reported eleven) presumed cartel gunmen and the detention of three men, including a Colombian national. The operation secured firearms, ammunition, tactical equipment and vehicles, which were handed over to the public prosecutor. Officials linked the assailants to the Los Chapitos faction of the Sinaloa Cartel and mentioned the targeted capture of Óscar Luciano Martínez Larios, alias “El Casco 81”. Secretary of Security Omar García Harfuch expressed condolences, saying, “We express our condolences to the family and recognize the marine’s dedication and courage.” President Claudia Sheinbaum confirmed the figures and pledged further investigation.