CNN

Researchers have discovered what they say is the earliest direct evidence of a shark attack on a human, with the sea creature inflicting some 790 injuries on a man 3,000 years ago.

Experts from the University of Oxford made the discovery while studying the remains of an adult male excavated from the Tsukumo site near Japan's Seto Inland Sea, which were covered in traumatic injuries to his arms, legs, front of chest and abdomen.

"We were initially flummoxed by what could have caused at least 790 deep, serrated injuries to this man," said researchers J. Alyssa White and Rick Schulting in a joint statement. "There were so many injuries and yet he was buried in the community burial ground, the Tsukumo Shell-mound cemetery site."

Some of the lesions were very sharp, deep, and V-shaped, and were similar to wounds caused by metal implements that weren't used by the Jōmon culture hunter-gatherers of this period, and terrestrial carnivores and scavenger tooth marks were also not consistent with the injuries.

"Through a process of elimination, we ruled out human conflict and more commonly-reported animal predators or scavengers," they added.

The shark species most likely responsible for the attack was either a tiger or white shark, researchers said.

Their findings were published Wednesday in the Journal of Archaeological Science: Reports.

The team worked with George Burgess, director emeritus of the Florida Program for Shark Research, to study forensic shark attack cases and put together a reconstruction of the rare case.

"There are very few known examples of shark attacks in the archaeological record," Schulting told CNN, adding that the earliest concrete example the team could find came from a late pre-Columbian site in Puerto Rico, dated to just before 1000 AD.

"The main reason that so few cases are known is simply because they were so rare," Schulting said. "Even today, with so many more people in the world, only a handful of lethal shark attacks occur each year."

After radiocarbon analysis the team concluded that the man died between 1370 BC and 1010 BC -- more than 3,000 years ago.

The team mapped the lesions onto a 3D model of a skeleton to visualize and analyze the injuries.

Experts think that the prehistoric hunter gatherer victim was alive at the time of attack due to the distribution of wounds, with his left hand missing, indicating a defense wound.

"We suspect that the man was probably out fishing with some companions in the Inland Seto Sea in southern Japan. They could have been fishing from a boat, or diving for shellfish," Schulting told CNN. "Perhaps they were even hunting sharks, as shark teeth are sometimes found in Jōmon archaeological sites.

"One or more sharks -- we suspect one but can't be certain about that -- attacked the man either while he was already in the water, or perhaps he lost his balance and fell, or was pulled overboard if the shark was on a fishing line -- this would not have been a small shark," he added.

Schulting said there were "so many tooth marks all over the skeleton" that the attack must have lasted "for some time."

The man's body was retrieved soon after the attack, and he was buried at the ceremony. He was also missing his right leg, and his left leg was placed on top of his body, researchers added.

Co-author Mark Hudson, a researcher with the Max Planck Institute, added in a statement that the case is a rare example of archaeologists being able to reconstruct a dramatic episode in the life of a prehistoric community.