A man was bitten by a shark and killed while fishing in a kayak in Hawaii.

 Patrick Briney of Stevenson, Wash., 57, was dangling his feet in the water while fishing with an artificial lure when a shark bit his leg, ABC 7 reported.

Briney's fishing partner heard him screaming.

"He paddled over and found him in that condition lying down. He applied a tourniquet on the leg that was wounded, and I guess somehow tethered his boat to his," William Dunaway, a witness, told ABC.

"He was missing his foot and his calf; most of it was torn off to the bone," Dunaway said. "We were all shocked. It was gruesome."

Before summoning a nearby charter boat to take them ashore, the victim's friend tied a tourniquet around his leg. Briney did not survive the trip back, CNN reported.

Medical experts are not sure what type of shark caused the fatal injury.

"We offer our condolences to the family of the victim. Our thoughts and prayers are with them," William J. Aila, Jr., of the Department of Land and Natural Resources (DLNR), said.

This is the 13th shark attack reported in Hawaii this year. This is a big jump from the four unprovoked attacks a year average the state has held for the past two decades.

"We are not sure why these bites are occurring more frequently than normal, especially around Maui," Aila said, CNN reported. "That's why we are conducting a two-year study of shark behavior around Maui that may give us better insights."

Aila said local officials are hopeful the frequency of attacks will drop in the near future. In August a German tourist died in Hawaii after a shark bit off her arm, CNN reported. The victim was snorkeling about 50 yards off the Maui shore when the attack occurred.

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