French TV Appeal Credited with Solving Cold Cases Through Public Engagement
Television appeals have proven effective in solving cold cases, with M6's program resolving six cases since 2021.
Event / Security
Dupont de Ligonnès Fugitive Case
Fifteen-year investigation into Xavier Dupont de Ligonnès, who fled France after the 2011 murders of his wife and four children in Nantes. Ongoing search for the fugitive with periodic leads and developments.
9 reported locations
Daily activity
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2026-08-17 to 2026-11-14 · UTC publication dates
Coverage begins 26 Mar, 08:55 UTC
Follow the documented timeline or explore the related reporting.
What happened
Bishop of Carcassonne denies authorizing priest to disclose Xavier Dupont de Ligonnès confession
On June 3, 2026, Bishop Bruno Valentin of the Diocese of Carcassonne and Narbonne publicly stated that he had never been contacted by the alleged priest or by M6 before the broadcast and characterized the televised sequence as 'totally false'. He declared that no priest named 'Father Marc' exists in the religious community in Plavilla and announced his intention to file a complaint with the Arcom, France's audiovisual regulatory authority.
Ouest-France identifies potential online account used by Xavier Dupont de Ligonnès until 2017
Ouest-France published an investigation on June 1, 2026, identifying an online account called 'Epsilon' on the forum cite-catholique.org that may have been used by Xavier Dupont de Ligonnès. The account was created in July 2010 and remained active until 2017, posting over 1,100 messages. Analysis using AI-based OSINT and stylometry identified similarities with accounts previously known to be used by Dupont de Ligonnès, including unusual capitalization patterns, repeated punctuation marks, recurring expressions like 'CQFD' and 'Liste non exhaustive', and references to obscure biblical figures previously mentioned in his writings.
M6 producers acknowledge being misled by false priest testimony on Xavier Dupont de Ligonnès
On June 3, 2026, Julien Courbet and Stan Vignon from M6 stated that the witness claiming to be a priest had misled them during the broadcast. Stan Vignon acknowledged that the person ultimately admitted he was not a priest after extended conversations during the program.
Bodies of Xavier Dupont de Ligonnès' wife and four children discovered in Nantes in 2011
The bodies of Xavier Dupont de Ligonnès' wife and four children were discovered buried under a terrace in Nantes in April 2011. Xavier Dupont de Ligonnès disappeared after the discovery and has remained a fugitive for fifteen years.
M6's 'Appel à témoins' program has resolved six criminal cases since 2021
According to Jean-Marie Goix, producer of the M6 program 'Appel à témoins' launched in 2021, six cases have been definitively resolved with assistance from the program: Lucas Tronche, Caroline Marcel, Laëtitia Manzano, Laura Bohan, Henda Djebali, and Margaux Ferréol. An additional case was resolved in late May 2026 with the conviction of a hit-and-run driver responsible for the death of Tessa Raimbault in 2018. The producer noted that law enforcement frequently requests call lists and content from the program, which leads to the reopening of many cases.
Man claiming to be priest reports confessing Xavier Dupont de Ligonnès in 2022
During the M6 television program 'Appel à témoins' aired on June 2, 2026, a man identifying himself as 'Father Marc' claimed to have harbored Xavier Dupont de Ligonnès in a monastery in the Aude department in 2022 and to have received his confession regarding the murders. The witness claimed the fugitive remained in the monastery for four days in a state of psychological distress before departing toward the Alpes-Maritimes, and asserted he possessed a photograph and telephone number belonging to Dupont de Ligonnès. The witness claimed to have received permission from the Bishop of Carcassonne to disclose the confession.
Bishop of Carcassonne denies authorizing priest to break confession seal regarding murder suspect
Bishop Bruno Valentin of the Diocese of Narbonne and Carcassonne issued a statement denying that he was ever contacted about the Xavier Dupont de Ligonnès case, nor was M6 television prior to broadcast. He stated that no priest named 'Father Marc' exists in the religious community in question and characterized the televised sequence as 'misleading to the public.' The bishop indicated he would file a complaint with the Arcom, France's audiovisual regulatory authority.
Bodies of Xavier Dupont de Ligonnès' family discovered buried under house terrace in Nantes
The bodies of Xavier Dupont de Ligonnès' wife Agnès and their four children—Arthur, Thomas, Anne, and Benoît—were discovered buried under the terrace of their house on boulevard Robert-Schuman in Nantes, Loire-Atlantique. Xavier Dupont de Ligonnès, the principal suspect in the killings, has remained missing since the discovery.
Man claiming to be priest appears on M6 television claiming to have confessed suspected murderer
A man identifying himself as 'Father Marc' appeared on the M6 television program 'Appel à témoins' and claimed to have confessed Xavier Dupont de Ligonnès in a monastery in the Aude region in 2022. He stated that the suspect spent four days at his religious community and confessed to murdering his family. The priest claimed to have received permission from the Bishop of Carcassonne to break the seal of confession to make these revelations public.
Television footage from 2025 shows man resembling suspected murderer on roadside in southern France
During the 'Appel à témoins' program, a video recorded in 2025 from a Tesla vehicle camera was broadcast showing a man on the side of a road in southern France who resembled Xavier Dupont de Ligonnès. The footage did not convince observers present on the program set.
M6 television program 'Appel à témoins' episode on murder case reaches 1.98 million viewers
The M6 television program 'Appel à témoins' episode focused on the Xavier Dupont de Ligonnès case aired on Tuesday, June 2, 2026, and was watched by 1,980,000 viewers for the segment on the case. The program featured testimonies from witnesses who claimed to have encountered the suspect in 2011 and the controversial testimony from the man claiming to be a priest.
Last confirmed sighting of Xavier Dupont de Ligonnès occurred in April 2011 in southeastern France
The last confirmed trace of Xavier Dupont de Ligonnès dates to April 15, 2011, at Roquebrune-sur-Argens in the Var department, where he abandoned his vehicle after spending the night at a Formule 1 hotel. Multiple testimonies during the television program indicated sightings of the man in late April 2011, and a car rental agency employee stated she encountered him as a potential client after this date, though he was unable to proceed without a valid bank card.
A 2019 arrest in Scotland in the Dupont de Ligonnès case turned out to be a case of mistaken identity
In 2019, a man was arrested in Scotland on suspicion of being Xavier Dupont de Ligonnès. The arrest was subsequently confirmed to be an error of identification, and the individual was released. No confirmed sighting of Dupont de Ligonnès has been made since his disappearance in 2011.
Retired French investigator Gilles Galloux published a book in February 2026 suggesting Dupont de Ligonnès fled to the US
Gilles Galloux, a former investigator from France's cybercrime division who was central to the digital manhunt for Xavier Dupont de Ligonnès, published a book in February 2026 titled 'Xavier Dupont de Ligonnès – Un flic au cœur de l'enquête.' Based on analysis of pseudonyms, IP addresses, and telephone data, Galloux suggests Dupont de Ligonnès may have fled to the United States and could be hiding in ghost towns near the Mexican border. His theory is disputed by official investigators due to lack of concrete evidence.
Xavier Dupont de Ligonnès disappeared in 2011 after his wife and four children were found murdered in Nantes
In April 2011, the wife and four children of Xavier Dupont de Ligonnès were found dead, buried under the terrace of their home at 55 boulevard Robert-Schuman in Nantes, France. Xavier Dupont de Ligonnès disappeared days before the bodies were discovered. He had emptied bank accounts, organized his departure, and sent letters to relatives suggesting a trip abroad. He has not been found since.
Xavier Dupont de Ligonnès reportedly sighted in southern Brewster County in 2020 with a black labrador
The Brewster County Sheriff's notice states that an individual matching the description of Xavier Dupont de Ligonnès was possibly observed in 2020 in the southern part of the county, near the Mexican border, accompanied by a black labrador. The photographs circulated are approximately 15 years old and described as the most recent available.
Brewster County Sheriff issues wanted notice for Xavier Dupont de Ligonnès in Texas
The Brewster County Sheriff's Office in Texas published a wanted notice on March 25, 2026, seeking information about Xavier Dupont de Ligonnès, the main suspect in a 2011 quintuple homicide in Nantes, France. The notice was shared via the sheriff's Facebook page and invites anyone with information to contact local authorities.
French investigators reject the American lead in the Dupont de Ligonnès case, citing no tangible evidence
French investigators have consistently rejected the hypothesis that Xavier Dupont de Ligonnès fled to the United States, stating they possess no tangible evidence of his presence there since his disappearance in April 2011. They remain cautious following a high-profile wrongful arrest in Scotland in autumn 2019, when a French retiree of Portuguese origin, Guy Joao, was mistakenly detained as the suspect before DNA analysis proved otherwise. Both the flight and suicide hypotheses remain open with no formal proof for either.
Retired French police officer Gilles Galloux publishes book asserting Dupont de Ligonnès is alive in the US
Retired French police officer Gilles Galloux, one of the first investigators on the 2011 Dupont de Ligonnès case, published a book titled 'Un Flic au cœur de l'enquête' (editions Max-Milo) in early 2026. In it, he asserts his conviction that Dupont de Ligonnès staged his disappearance, did not commit suicide, and fled to the United States — a country the suspect was reportedly passionate about and familiar with. Galloux claims to have contacted American women who knew Dupont de Ligonnès in his youth and to have identified a ranch and a woman of interest.
Xavier Dupont de Ligonnès allegedly spotted in 2020 in Brewster County with a black labrador
The Brewster County Sheriff's Office stated that Xavier Dupont de Ligonnès may have been observed in 2020 in the south of Brewster County, Texas, accompanied by a black labrador. The sheriff's office emphasised that no confirmed sighting or testimony had been registered in the area, and that the appeal was precautionary rather than based on a confirmed lead.
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2 alternative perspectives
Ouest-France traces online account potentially linked to fugitive until 2017
Ouest-France identified a potential online account linked to the suspect until 2017.
Priest's Confession Claim Unravels as Bishop Denies Authorization
Television priest claim debunked after bishop denies authorization and network admits deception.
M6 Television Appeal Reaches Nearly 2 Million Viewers in Murder Case
M6 murder case appeal broadcast reached nearly 2 million French television viewers.
Priest claims confession from suspect; bishop disputes authorization
Priest claims confession from suspect; bishop denies authorization for seal-breaking disclosure.
Timeline Emerges: From 2011 Disappearance to 2025 Roadside Sighting
Alleged sighting in 2025 adds new chapter to 14-year search beginning with 2011 family discovery.
Texas Sheriff's Wanted Notice Rooted in 2020 Sighting and Decades-Old Crime
Texas issued a wanted notice for Dupont de Ligonnès after a 2020 sighting, linked to his 2011 disappearance following murders in France.
French Investigators Dismiss US Lead Despite Texas Sighting Reports
French investigators reject the US lead, despite a Texas sighting report and a retired officer's book claiming otherwise.