On September 1, 2026, a multiple homicide shocked Mexico and Argentina. In an apartment in Atizapán de Zaragoza, State of Mexico, the bodies of Jonathan Meléndez Ochoa (38), keyboardist and founder of the band Camilo Séptimo; his wife Ana Paula Barragán (35), who was four months pregnant; their daughter Sofía, aged 3; and the nanny Aleyda Romero were found. The family dog was also found tied up and dead.
Amid the tragedy, a story of survival emerges: the couple's eldest son, aged 6 (some sources say 5), managed to save himself by hiding during the attack, following the nanny's instructions. He remained hidden for more than three hours until municipal police rescued him around 11:50 PM, showing no signs of violence.
The Accused: Diego Sebastián Rosen
Diego Sebastián Rosen, born in Buenos Aires on March 26, 1975, and naturalized Mexican in 2001, was arrested as the alleged perpetrator. At 51 years old at the time of the events, Rosen had maintained a business profile in Mexico for over two decades, with ventures ranging from pharmaceutical marketing to luxury vacation rentals.
According to the National Population Registry, he obtained his naturalization card in 2001. That same year, he founded Ferlini, Rosen y Asociados, dedicated to the sale of printed materials and medical equipment. In 2003, he began operating Shark BTL, a marketing agency in Polanco, and in 2008, he founded Medical Branding de México. His history includes the creation of CAFADE (ATMs) in 2012, Huerto Capital (urban gardens) in 2013, and Fifty Fifty Total Production in 2018, the latter alongside his romantic partner, Argentine Paola Mandri Figueroa.
The Link with the Victim: Vacation Rentals
Rosen and Meléndez shared a business of luxury vacation home rentals in Valle de Bravo, Tepoztlán, Acapulco, and Cuernavaca, operated under the name +Relax and later Nomad Property Management. They managed 32 properties in Valle de Bravo, with prices ranging from 7,000 to 50,000 pesos per night. This business was never formalized in any of the five companies registered by Rosen.
The financial dispute would be the motive for the crime. According to the investigation, Meléndez demanded 30 million pesos in cryptocurrencies from Rosen. The day before the murder, Meléndez asked a friend named “Freddy” to alert authorities if he stopped hearing from him, due to financial differences with Rosen.
The Massacre: Planning and Execution
Security cameras recorded Rosen entering the building at 5:24 PM. Ana Paula opened the door, as Meléndez had not yet arrived. Rosen took advantage of the trust relationship to access the home. He used a 9mm pistol with a silencer. The victims were found with their hands tied; two had gunshot wounds to the head, and one (the nanny) had a gunshot wound to the back.
The planning was meticulous: Rosen asked his accomplice, Gerardo “N”, his driver, to obtain industrial adhesive tape, heavy-duty black gloves, and plastic zip ties, paying in dollars. Gerardo “N” was arrested in Tecámac. According to journalist Antonio Nieto, Rosen left the driver's license of the chauffeur in the building to incriminate him.
Attempt to Flee and Arrest
After the crime, Rosen changed the plates of his gray Kia for those of a Chevrolet Onix. However, the escape route was reconstructed using C4 and C5 cameras. He was arrested on the Mexico-Toluca highway, at La Marquesa, Ocoyoacac, along with his accomplice. Both were placed at the disposal of the Special Affairs Prosecutor's Office of the State of Mexico.
Transfer to Prison and Background
On September 4, 2026, Rosen was transferred to the Barrientos Social Reintegration Center in Tlalnepantla, from the Central Complex of the State of Mexico Prosecutor's Office, before the constitutional deadline expired at 10:00 AM.
Rosen had no criminal record in Argentina, but in Mexico he had a complex legal history: amparos (injunctions) against arrest warrants in 2017, 2023, and 2024, and an arrest warrant in December 2025 for an unspecified crime. Additionally, he faced fraud complaints in the vacation rental business, with allegations accumulating up to 2,000,000 pesos in scams.
Key Case Facts
- Victims: Jonathan Meléndez (38), Ana Paula Barragán (35, pregnant), Sofía (3), Aleyda Romero (nanny), and the family dog.
- Survivor: 6-year-old son, rescued unharmed.
- Date of Crime: September 1, 2026.
- Arrest: September 4, 2026, in La Marquesa.
- Motive: Financial dispute over 30 million pesos in cryptocurrencies.
The artistic community and fans of Camilo Séptimo have expressed their grief over the loss. The band, known for hits like “No voy a llorar,” loses one of its founders in an event that shakes both countries. Mexican justice is moving forward with the case against Rosen, who faces charges of aggravated homicide.