A French news agency reported that a boy's body was found by bathers in the water south of Porquerolles at around 5pm.
Toulon prosecutor Xavier Tarabeux told Agence France Presse (AFP): "The body matches that of the young boy who went missing on Saturday."
He said the physical appearance matched as well as the clothes.
The agency reported that the body was found by Langoustier bay to the south of the island, not far from where Pierre's bike was discovered.
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Heavy and thundery showers will die out in most places during the evening, but may continue near the Humber for most of the night.
Showers will slowly clear overnight. Any mist and low cloud will clear during the morning, leaving bright or sunny spells.
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