iStock/Thinkstock(NEW YORK) — The bites that a 13-year-old boy sustained in the waters around the barrier island off Long Island’s South Shore resulted from a shark attack, New York state officials confirmed on Friday.

But experts have been unable to determine the species based on the size and condition of a tooth fragment recovered from the boy, authorities said, adding that the state Department of Environmental Conservation (DEC) will return it to the teen at his request.

The beaches on Fire Island had reopened Thursday morning, a day after the boy and a 12-year-old girl suffered large fish bites in the area.

Lifeguards were on duty from 11 a.m. at Atlantique Beach, where the 13-year-old boy, Matthew Donaldson, was bitten. The National Park Service surveyed Sailors Haven Beach, where the 12-year-old girl, Lola Pollina, was bitten, and reopened that beach. The two beaches are fewer than 5 miles apart.

The DEC made no mention of Lola’s bites.

New York Governor Andrew Cuomo had dispatched Basil Seggos, the DEC commissioner, to Suffolk County to investigate whether it was indeed a shark that had bitten the two children.

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