The case that shocked Mexico: The investigation into the murders of Jonathan Meléndez and his family

As Mexico searches for answers to one of the country’s most shocking crimes in recent years, little is known about the man accused of carrying it out. The hard facts about the man in custody amount to little more than a handful of biographical details. Diego Sebastián Rosen Ferlini is an Argentine national and, according to his passport, 51 years old. During his years in Mexico, he founded five companies, the first in 2001 and the most recent in 2018, according to the Public Registry of Commerce.

He was also a business partner of Jonathan Meléndez, according to Mexico’s security chief Omar García Harfuch. Security camera footage from an elevator shows him arriving at a building in the Grand Viure residential development at 5:24 p.m. on Tuesday. He was arrested the following day at 9:25 a.m. in the municipality of La Marquesa, according to the National Detentions Registry.

He is the prime suspect in a massacre: the killings of Meléndez, 38, keyboardist and founder of the band Camilo Séptimo; his partner, Ana Paula Barragán, 35, who was four months pregnant; their three-year-old daughter, Sofía; and Aleyda Romero, 21, who worked in the household. Diego Sebastián Rosen Ferlini has become the face of a crime that has shocked an entire country.

So far this year, and before August figures have been released, 10,309 people have been killed in Mexico, according to data from the Executive Secretariat of the National Public Security System. Six percent of those victims, 618 people, were murdered in the State of Mexico, where Meléndez and his family were killed on Tuesday. Yet it is the brutality of the Atizapán murders that has stirred something in a country that struggles daily under the weight of violence. It does not happen often, but Mexico has been shaken.

On Wednesday, further details of the case became public: Jonathan and Ana Paula had been tied up; Sofía was shot from the front and Aleyda in the back; the family’s dog was also killed; the couple’s six-year-old son of the couple; police arrived shortly after 11 p.m.; and Rosen Ferlini was arrested roughly 10 hours later.

Since then, dozens of reports have been published about the companies owned by the suspect, the gated community where the crime took place, Ana Paula’s life, and the history of Camilo Séptimo. Argentine newspapers Clarín and La Nación have reported that Rosen Ferlini had no criminal record in Argentina, no pension contributions, debts or registered profession. They traced a tax address to the Buenos Aires neighborhood of Saavedra and found that his last trip to Argentina was in February 2020. Since the massacre came to light, nearly every detail has revolved around the same unanswered question: why would someone commit a crime like this?

On the official side, García Harfuch wrote on X that, because Meléndez and Rosen Ferlini were business partners, the Argentine “allegedly took advantage of that relationship of trust to gain entry to the home.” In an interview with W Radio on Thursday, he described the killings as a “truly atrocious crime” that shocked even some of the officers involved in the operation to apprehend the suspects. “The initial investigation indicates that it was entirely a matter of money, of debts between them,” he said of the victim and the alleged killer.

Mexico’s president, Claudia Sheinbaum, referred only briefly to the case after being asked about it during her morning press conference on Thursday. “I was informed yesterday. It is indeed a very sad and tragic situation. There are already people in custody, and the reasons behind a dispute between one family and another are now known. The government of the State of Mexico is providing support to the families, and we will do what we can from the Interior Ministry,” she said.

According to the arrest report, Rosen Ferlini is being held “in transit” at a facility belonging to the State of Mexico Attorney General’s Office in Toluca, the state capital. He has not yet appeared before a judge, has not been formally charged, and has not so far been transferred to prison. The other detainee, identified as Gerardo N., is the driver who took Rosen Ferlini to the apartment in Atizapán.

Meanwhile, nearly 66 miles from the scene of the crime, a wake was held on Thursday. Surrounded by flowers, incense and banda music in San Martín Cuautlalpan, in the municipality of Chalco, family and friends gathered to say goodbye to Aleyda Romero. Her mother, Conchita, wept over the coffin. “Why you?” she cried.

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