Antoine de Massy, a cousin of Prince Albert II, was found dead in a Monaco garden.

The communique France 3 printed does not mention a nightclub and does not give the man a nationality. The Daily Mail, citing AFP, said de Massy was last seen staggering out of a nightclub early Sunday. L'Est Républicain, citing Monaco-Matin, reported that account and wrote that the prosecutor declined to comment on it. Monaco-Matin placed the body behind Villa Sauber. The Daily Mail placed it behind the New National Museum. The prosecutor's line is a park below the boulevard. He has not named a charge. The cause of death is what the investigation was opened to determine.

France 3 reported that Monaco Prosecutor General Stéphane Thibault said in a communique on Monday, Oct. 26, 2026, that after an alert from his family and a search by the Public Security Department, the body of Antoine de Massy was found early Sunday evening in a park below Boulevard du Larvotto. Sunday was Oct. 25. France 3 reported he was 29, the son of Baron Christian de Massy and Cécile Gelabale, and the grandson of Princess Antoinette, the elder sister of Prince Rainier III, which made him a petit-cousin of Prince Albert II. The Daily Mail reported the same relationship in English as first cousin once removed, and reported that the family alert was a missed family lunch, citing Monaco-Matin. Monaco-Matin reported that a relative went to public security over that lunch and that the body was found hours later in a green space along Boulevard du Larvotto, behind Villa Sauber. The Daily Mail placed the garden behind the New National Museum, along the same boulevard. The communique, as France 3 printed it, names the park below the boulevard and does not name a building.

France 3 reported that the communique said the inquiry, opened to determine the cause of death, quickly showed that a man had made contact with de Massy while he was still along Boulevard du Larvotto. The man was identified and arrested Monday morning to be questioned, and his custody was extended by 24 hours. France 3 quoted the communique: "Il ne s'agit à ce stade que d'un suspect, témoin des faits dont la qualification reste à déterminer." In that line he is, at this stage, only a suspect and a witness to facts whose legal classification remains to be determined. France 3 reported that the prosecutor said every hypothesis is being considered, including a simple accident. The Daily Mail reported that the prosecutor's office said the man's role remained unclear and that all possibilities, including an accident, were being considered, and that police on Monday arrested a Ukrainian national seen on CCTV near the body. L'Est Républicain reported that the prosecutor's office said a Ukrainian had been placed in custody, and, citing Monaco-Matin, described him as a Monegasque resident of Ukrainian nationality. The communique as France 3 printed it does not state a nationality. L'Est Républicain, citing Monaco-Matin, reported that de Massy had been seen leaving a nightclub in the principality, staggering, in the night from Saturday into Sunday, and that the prosecutor declined to comment on that account. The Daily Mail attributed the same nightclub account to AFP. No outlet cited here has named the man in custody.

The Daily Mail reported a palace statement on Monday: "Their Serene Highnesses Prince Albert II and Princess Charlène were saddened to learn of the death of Antoine de Massy, the grandson of Princess Antoinette, the elder sister of Prince Rainier III." The Daily Mail reported the statement continued, "A keen tennis player, he was part of a family history closely linked to the sport in the Principality," and, "Their Highnesses share in the grief of his family and loved ones and offer them their sincere condolences at this painful time." France 3 reported that the prince and Princess Charlène expressed their "tristesse," quoted the tennis sentence from the communique, and reported that they joined in the grief of his family and loved ones and offered sincere condolences. Those are two renderings of the palace statement. They are not a finding about how he died.

The open questions are the ones the prosecutor listed. The cause of death has not been stated. The man in custody has not been named, and the prosecutor has not described a charge. All defendants are presumed innocent until proven guilty in a court of law.