The shark that killed a woman in a rare attack off the coast of Maine, New England, was a great white, authorities have confirmed.
Julie Dimperio Holowach, 63, from New York City, died from her injuries after being bitten off Bailey Island on Monday while she was swimming.
Scientists later identified the shark as a great white using a tooth fragment, state officials said.
Great whites are not common in Maine, which is the northern tip of their range, but there have been reports of sightings in recent years.
A witness saw Ms Holowach swimming off the shore of Bailey Island when she was bitten, the Maine Marine Patrol said.
Two kayakers helped her get to shore and emergency workers provided further assistance, but she was pronounced dead at the scene.
The last unprovoked shark attack in Maine was recorded 10 years ago off Eastport, and involved a different species of shark, Maine Marine Resources commissioner Patrick Keliher said.
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Mr Keliher described Monday’s attack as “highly unusual”, but said beachgoers should be vigilant.
“The rarity of this event does not mean it’s not going to happen again,” he said.
The people who helped Ms Holowach were a man and woman in a rented tandem kayak, according to Jeff Cooper, co-owner of H2Outfitters on the island, which offers instruction, rentals and sales of kayaks.
They were on the shore when one of them saw something breach and quickly realised something was wrong, Mr Cooper said.
“They happened to be right there at the scene. They were courageous enough to jump in and retrieve the victim,” he said.
One of the kayakers, who have asked not to be identified, grabbed Ms Holowach while the other paddled to get her back to shore.
Rob Beal, major of the Maine Marine Patrol, said the community has been shaken by the death of Ms Holowach, who owned property in the area with her family and was well known.
The Maine Patrol has urged swimmers and boaters to use caution near Bailey Island and to avoid swimming near schooling fish or seals.
Bailey Island is part of the town of Harpswell, around 40 miles up the Maine coast from Portland.