Argentine Businessman Detained in Connection with Quadruple Homicide of Musician and Family in Mexico

Mexican authorities have detained Diego Sebastian Rosen, a 51 year old Argentine businessman, and another man identified as Gerardo N for their alleged roles in the murder of musician Jonathan Melendez Ochoa and three other people. The victims include Melendez, a keyboardist and producer for the band Camilo Septimo, his wife Ana Paula Barragan who was four months pregnant, their three year old daughter, and a 21 year old domestic worker. A six year old boy was the sole survivor of the attack, which occurred at the family residence in Atizapan, within the Mexico City metropolitan area. The family dog was also killed.

Investigators from the Fiscalía General de Justicia del Estado de México and the Secretaría de Seguridad Ciudadana report that the victims were killed with firearms. The musician and his wife were found bound, as was the family pet. The young daughter suffered a gunshot wound to the head, while the domestic worker was shot in the back. Security Secretary Omar Garcia Harfuch stated that Rosen was a business partner of Melendez and likely used this relationship of trust to enter the home without forcing entry.

Evidence against Rosen includes security footage from the building elevator. The video shows Rosen wearing a cap, dark glasses, and a backpack; he is seen looking directly into the camera before exiting the elevator. Rosen was arrested on the Mexico Toluca highway in the area of La Marquesa.

Rosen operated a travel and vacation rental business under names including NOMAD Adventures, Nomad PM, and +Relax. Following his arrest, reports emerged of alleged fraudulent activities linked to these businesses. Some sources cite social media warnings from July 2026 accusing him of defrauding clients of approximately 400,000 to 500,000 Mexican pesos for rentals in destinations such as Valle de Bravo, Acapulco, and Tepoztlan.