Key facts
- Antoine de Massy, 29, a member of Monaco's princely family, was found dead on Sunday.
- A man seen near the scene shortly before de Massy's death was detained.
- The cause of death has not yet been determined, with all hypotheses considered.
Authorities in Monaco detained a man and opened an investigation into the death of Antoine de Massy, 29, a member of the princely family. His body was discovered on Sunday evening in a park. The prosecutor's office stated that all hypotheses, including a simple accident, are being considered. De Massy was the grandson of Princess Antoinette, the elder sister of Prince Rainier III, who was the father of Prince Albert II. Prince Albert II and Princess Charlene expressed their shock and condolences.