(CNN) -- The ocean water around Chatham, Massachusetts, is playing host to some unwelcome guests this holiday weekend: sharks. Only 41 unprovoked shark attacks have been reported in the U.S. since 2008. At least one large shark sighting was confirmed Friday by Greg Skomal, shark expert for the state's Division of Marine Fisheries. That sighting occurred off the eastern shore of Monomoy Island, a National Wildlife Refuge off the southern elbow of Cape Cod, according to Lisa Capone, Massachusetts Department of Energy and Environmental Affairs press secretary. The species, though not confirmed, was "most likely" a great white shark, she said.
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Shark expert confirms at least one large shark sighting Friday
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Species unconfirmed, but "most likely" was a great white, expert says
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As many as five large sharks were seen on Thursday near Monomoy Island
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Expert: On average, sharks kill about four people per year, worldwide
The last fatal shark attack in @placeholder occurred in 1936.