(CNN) -- It's official: It was a great white shark that bit a man's legs last week just off the coast of Truro, Massachusetts.
"This conclusion was reached after examination of the injuries and testimony from (the victim)," said Reginald Zimmerman, a spokesman for the office of Energy and Environmental Affairs.
Chris Myers and his teenage son were swimming toward a sandbar about 500 yards off Ballston Beach. They wanted to body surf where the waves were breaking.
"Apparently I was the only one on Cape Cod who hadn't heard of the shark sightings," Myers told CNN's Piers Morgan on Tuesday night.
Reports of shark sightings have gone up off the coast of Massachusetts in recent years, especially around areas where seals congregate.
But just after the pair decided to turn around, something bit the man's leg.
"I figured it was either an elephant ... or a polar bear ... or a shark. So pretty quickly I got to shark," Myers jokes. "It felt like I was in a very, very heavy vise."
The great white shark then surfaced between father and son, who were about 6 feet apart, arching its back as if intentionally showing itself to them, he said.
The shark slipped under the waters, and the men swam back to shore where they were helped by a doctor and a nurse who happened to be on the shoreline.
Myers was composed until he realized he had survived a great white shark attack. He had only one word to describe that moment: "euphoria."
The physical damage caused by the shark was far less than it could have been. Myers has a cast on his left leg because his tendons were severed and 47 stitches on his right leg, where the teeth of the shark left several puncture wounds.
Great white sharks range from 12 to 21 feet and weigh nearly 3 tons. They are believed to live longer than 30 years.
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