Solved case · 2023
The short answer
Cecilia Strzyzowski, a 28-year-old woman from Resistencia, Chaco, Argentina, disappeared on 2 June 2023 after being seen entering the home of her partner César Sena. She was later found to have been murdered in a femicide involving Sena and members of his politically influential family, the "Sena Clan." In November 2025, six defendants were convicted of murder while one was acquitted.
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Suggest coverage for Murder of Cecilia StrzyzowskiCecilia Marlene Strzyzowski, born 3 August 1994, was an administrative employee at a health center and cafeteria owner in Resistencia, Chaco Province, Argentina. She was in a relationship with César Sena, whom she had married in September 2022 before beginning divorce proceedings four days later; the couple reportedly continued their relationship despite the unfinalized divorce. On 1 June 2023, Cecilia told her mother, Gloria Romero, via video call that she and Sena planned to travel to Ushuaia for a job opportunity. She was last seen leaving her aunt's house with Sena that afternoon. Security footage showed her entering the Sena family residence on 2 June, with no recorded departure and the final signal from her mobile phone traced to that location.
Romero filed a missing-person report on 6 June after receiving anonymous information suggesting harm had come to her daughter. The Chaco Prosecutor's Office activated a missing-persons and gender-violence protocol, and the case was soon reclassified as a suspected femicide. Investigators identified César Sena's parents, Emerenciano Sena and Marcela Acuña — social leaders and provincial election candidates with described ties to the Chaco provincial government — as principal suspects alongside César. Searches of Sena family property recovered bone and blood remains later matched to Strzyzowski's DNA, along with a butcher's saw, a machete, and ammunition. Additional searches of the Tragadero River recovered crushed bone fragments and a pendant identified by Romero as belonging to her daughter.
According to prosecutors, Strzyzowski was killed at the Sena residence on 2 June between approximately 12:13 and 1:01 p.m. by César Sena and his parents, after which associates Gustavo Obregón and Fabiana González allegedly assisted in destroying evidence. Prosecutors said the body was later taken to a rural property, dismembered, cremated, and the remains disposed of in the river. Gustavo Melgarejo, the Senas' landlord, and his partner Griselda/Graciela Reynoso were also charged in connection with concealment; Melgarejo told investigators he had seen Strzyzowski restrained in a vehicle belonging to Emerenciano Sena before her death.
The case drew national and international attention, including a campaign by Amnesty International, and was widely reported to have influenced the outcome of the 18 June 2023 Chaco provincial elections, in which Emerenciano Sena, Acuña, Obregón, and González had been candidates before being removed from ballots following the scandal. Separate investigations were opened into alleged money laundering and undeclared cash tied to the Sena family, and into an alleged attempt to arrange favorable treatment from a judge. Family members, their lawyer, and journalists covering the case reported threats and intimidation during the investigation.
On 15 November 2025, a verdict was delivered: six defendants — César Sena, Emerenciano Sena, Marcela Acuña, Gustavo Obregón, Fabiana González, and Gustavo Melgarejo — were convicted of murder-related charges, while Graciela Reynoso was found not guilty.
Cecilia Strzyzowski and César Sena begin a relationship, reportedly meeting through a dating app.
Cecilia Strzyzowski and César Sena marry; divorce proceedings begin four days later.
Cecilia tells her mother via video call she is traveling to Ushuaia with César Sena for a job opportunity; she is later seen leaving her aunt's house with Sena.
Security cameras record Cecilia entering the Sena family residence; no departure is recorded, and her phone's last signal is traced to the location. Prosecutors later allege she was killed there this day.
Anonymous individuals contact Cecilia's family suggesting something happened to her; communication with her subsequently becomes limited to text messages.
Gloria Romero files a missing-person report; the Prosecutor's Office activates a missing-persons and gender-violence protocol.
César Sena is summoned to testify and is seen with scratches on his neck; he becomes a fugitive after failing to appear as required.
Raid on the Sena family home recovers blood stains and undeclared cash; prosecutors request the arrest of Emerenciano Sena and Marcela Acuña.
César Sena surrenders to police; Fabiana González and Gustavo Melgarejo are arrested.
Gustavo Melgarejo and his partner Griselda/Graciela Reynoso are arrested on suspicion of assisting in disposing of the body; Fabiana González and Gustavo Obregón are also arrested.
Prosecutors reclassify the case as femicide; suspects are charged as co-authors of aggravated homicide.
Chaco provincial elections are held; media report the case influenced results, contributing to a win for the opposition.
Search of the Tragadero River recovers crushed bone fragments and a pendant identified as belonging to Cecilia Strzyzowski.
Presence of Cecilia Strzyzowski's burned remains in the Sena family patio is confirmed.
Verdict delivered: six defendants convicted of murder-related charges; Graciela Reynoso acquitted.
Victims first. Every legal label is set from public records and court outcomes, not from the prose.
28-year-old woman murdered in a femicide in Resistencia, Chaco, Argentina, in June 2023.[3]
Victim's partner; convicted of murder aggravated by the bond, premeditated collaboration of two or more people, and gender violence context.[3]
César Sena's father; convicted of aggravated homicide as co-author.[3]
Collaborator and associate of the Acuña and Sena family; convicted of aggravated homicide as a necessary participant.[3]
Landlord of the Sena family; convicted in connection with aggravated concealment as a secondary participant.[3]
Political associate of the Sena/Acuña family; convicted of homicide aggravated by premeditated participation of two or more people as a secondary participant.[3]
César Sena's mother; convicted of aggravated homicide as co-author.[3]
Partner of Gustavo Melgarejo; charged with aggravated concealment as a secondary participant and found not guilty.[3]
Prosecutor supervising the investigation for the Special Prosecutor's Office for Gender Violence No. 4.[3]
Prosecutor supervising the investigation for the Special Prosecutor's Office for Gender Violence No. 4.[3]
Prosecutor supervising the investigation for the Special Prosecutor's Office for Gender Violence No. 4.[3]
From the record
Coverage is not a source: every fact in this file rests on the records below.
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UNSOLVEDListenNapalpí, Chaco Province, Argentina · 1920s
On 19 July 1924, Argentine police, ranchers, and armed civilians attacked Indigenous Toba and Mocoví residents of the Napalpí colony in Chaco Province, killing an estimated 400 people in a massacre later declared a crime against humanity.
Credit: Victims' photographs as circulated in Turkish press (via Türkiye Today)Editorial useSourceSOLVEDListenWalls of Constantinople, Fatih, Istanbul, Turkey · 2024
On 4 October 2024 in Istanbul, 19-year-old Semih Çelik, identified by police as the attacker, killed Ayşenur Halil and İkbal Uzuner, both 19, within half an hour of each other, then died by suicide; the public murder-suicide sparked nationwide protests over femicide in Turkey.
Credit: ProtoplasmaKidCC BY-SA 4.0SourceSOLVEDListenGustavo A. Madero, Mexico City, Mexico · 2020
Ingrid Escamilla Vargas, a 25-year-old woman, was murdered by her boyfriend in Mexico City on 9 February 2020 in an act of femicide. He was later convicted and sentenced to 70 years in prison. The case sparked national outrage after graphic images of her body were leaked to tabloid media and social networks.
SOLVEDListenYerkesik, Menteşe, Muğla Province, Turkey · 2020
Pınar Gültekin, a 27-year-old university student in Muğla, Turkey, disappeared on 16 July 2020 and was found murdered days later, her body burned and encased in concrete. The case sparked nationwide protests and revived the global #ChallengeAccepted campaign against femicide.
SOLVEDListenBuenos Aires, Argentina (kidnapping site); Timote, Buenos Aires Province (killing site) · 1970
Former de facto Argentine President Pedro Eugenio Aramburu was kidnapped from his Buenos Aires apartment on 29 May 1970 by members of the far-left guerrilla group Montoneros and shot to death three days later on 1 June 1970.
Credit: Roblespepe. Using this public-domain dataset for the relief: ETOPO1 Global Relief ModelCC BY-SA 4.0SourceSOLVEDListenSouth Atlantic Ocean, off the coast of Argentina · 2017
The Argentine Navy submarine ARA San Juan disappeared in the South Atlantic on 15 November 2017 during a training exercise, with 44 crew members aboard. Despite a large multinational search, the vessel was not located until 16 November 2018, when the private company Ocean Infinity found its wreck at a depth of 907 metres. All 44 crew were lost.
