A man remains in police custody in Monaco after Antoine de Massy, a 29-year-old relative of Prince Albert II, was found dead in a public garden in the principality’s Larvotto district on Sunday.
De Massy’s family reported him missing after he failed to attend a family lunch that day. His body was later discovered in a garden below Boulevard du Larvotto, near the 21 Princesse Grace residence.
Monaco police arrested the man on Monday morning after reviewing security camera footage showing him walking with de Massy shortly before his death. His detention was extended by another 24 hours as investigators continued questioning him and examining evidence.
Monaco’s prosecutor general said the man is being treated as a suspect and witness while authorities work to establish what happened. Investigators have not determined the cause of death, and an accident has not been ruled out. The man’s involvement in the circumstances surrounding de Massy’s death has not been established.
De Massy was the son of Baron Christian de Massy and Cécile Gelabale, and a grandson of Princess Antoinette, the sister of former Prince Rainier III. Prince Albert II succeeded his father as Monaco’s head of state in 2005.
Albert and Princess Charlene expressed their condolences to de Massy’s family, describing him as a keen tennis player whose family had longstanding ties to the sport in Monaco.
De Massy developed a passion for tennis as a child and later moved to Miami with his father to train in hopes of representing Monaco at the 2016 Olympic Games in Rio de Janeiro. His grandfather, Alexandre-Athenase Noghès, was an international Monegasque tennis champion, while his aunt, Elizabeth-Ann de Massy, led the Monegasque Tennis Federation.
De Massy later studied international relations at Florida International University and co-founded the business app startup Instant App in 2021.