The island, which sits on the so-called "Shark Highway" between South Africa and Australia, has had 10 fatal shark attacks since the year 2000.
A missing British tourist is believed to be dead - after a hand wearing his wedding ring was found inside the stomach of a shark.
The 44-year-old Scot is believed to have been on a week-long holiday with his wife in Saint-Gilles, and according to witnesses had not been in the water long when he disappeared.
The victim, identified as civil servant Richard Martyn Turner, from Edinburgh, was snorkelling by himself in waters off the Reunion Island, a French department in the Indian Ocean, where four sharks were later caught, The Daily Mail reported citing Scottish media reports as saying. Mrs Turner reported her husband missing after he failed to return from the water.
"We are providing support to the family of a British man who died while snorkeling in La Reunion and are in contact with the local authorities", a spokesman said.
It was still unknown if the man got attacked by the shark, or he drowned and got eaten by a shark, thinking he was food.More news: Galaxy Fold Immediately Sells Out Online in China
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Divers also took part in the searched, as well as patrols on land involving sniffer dogs.
An autopsy of one of the sharks revealed the man's fate.
The tourist's remains were only found after local researchers pulled five sharks from the Indian Ocean to study on Monday and Tuesday, The Guardian reported.
Shark attacks - mostly by bulls and tigers - increased 23-fold on the island between 2005 and 2016, researchers have said, pointing to a boom in development and the volcanic origins as two contributing factors.
DNA tests are due to be carried out on the hand, but scientists from the CSR Shark Safety Centre on Reunion have been told that the wedding ring "conformed to one identified by the man's wife", said the source.