EDGARTOWN, Mass. (AP) — Lifeguards have whistled in swimmers off the coast of Martha’s Vineyard after beachgoers reported sightings of a shark only about 5 feet from shore.

Some suspected the animal spotted Wednesday close to the Massachusetts coast was a hammerhead shark, about 10-feet-long.

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But John Chisholm, a state marine fisheries biologist, says he doubts that because it would be out of the ordinary for a hammerhead to swim so close to shore.

Swimmers were advised to stay out of the water at nearby beaches.

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Swimmers were called out of the water at South Beach in Edgartown, Aug. 3, 2016. (Photo credit: Steve Newcomb)

Swimmers were called out of the water at South Beach in Edgartown, Aug. 3, 2016. (Photo credit: Steve Newcomb)

Jessica McGroarty, parks administrator for Edgartown, says swimming was first suspended for about an hour and a half after a spotter pilot confirmed the presence of the shark.

After the water was reopened to swimmers, it was closed again for a half-hour following a second sighting.

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