The French police have launched a murder investigation after the discovery of the bones of at least four individuals near the foot of a cliff at Cap d’Antibes, near Cannes. Amongst the bones is the humerus, or upper arm bone, of Stéphane Hirson, the 17-year-old who has been missing since 1994.

The skull, discovered by a diver whilst he was searching for urchins, bears a handwritten inscription in indelible marker, which reads: ‘Mort aux pédophiles’ (‘Death to paedophiles’). Alongside the inscription a mark has been drawn, believed to depict a shooting target.

The diver made his unpleasant discovery just six meters below the surface of the water and approximately a hundred metres from a popular coastal path. Police divers subsequently combed the area and retrieved a further four bones; a femur (thigh bone), two humerus bones, and a piece of a jaw bone.

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DNA results have shown that the bones belong to at least four separate victims; two men and two women. One of these individuals has been identified as Stéphane Hirson, the teenager who went missing days before his 18 birthday almost twenty years ago. The identity of the other victims remains unknown, but it is clear that both female bones are those of women under 30. The second man, to whom the skull belongs, has been shown to be under the age of 50. DNA tests on the piece of jawbone have been inconclusive, meaning there could be a fifth victim in the case. Although the bones are in good condition, investigators believe they have been under water for over a decade.

Georges Gutierrez, the prosecutor in neighbouring Gasse, announced the opening of the police inquiry on Wednesday. He stated that there are many enigmas to be solved. For example, "Why was there only one bone per individual and not more parts of the skeleton?"

Hirson went missing in 1994 after being released from a short stay in a psychiatric hospital. A family member has pointed out that he had no reason to be anywhere near Cap d’Antibes, as he was on his way to Spain. An attempt to link known paedophiles to the inscribed skull has not yet yielded any results.

Further DNA tests are ongoing, and additional dives in the area are being considered.