The famed Tyrannosaurus rex might have been even more horrifying than we thought. New research suggests the giant dinosaur had cannibalistic tendencies.

Recently discovered tyrannosaur bones were covered in teeth marks that suggested the dinosaurs munched on their own kind, the Geological Society of America reported.

"We were out in Wyoming digging up dinosaurs in the Lance Formation," said paleontologist Matthew McLain of Loma Linda University in California. "Someone found a tyrannosaur bone that was broken at both ends. It was covered in grooves. They were very deep grooves."

The grooves are believed to have been caused by an animal pulling the flesh off the bone at an angle perpendicular to the bone, similar to the way a human would eat a piece of fried chicken. One groove in particular that was located at the end of the bone and displayed smaller parallel grooves appeared to have been caused by the diner turning its head and dragging its serrated teeth across the bone. The evidence of large serrated teeth suggests the creature munching on the dinosaur was another tyrannosaur.

"This has to be a tyrannosaur," McLain said. "There's just nothing else that has such big teeth."

The pattern of the grooves also suggests the victim was already dead when it was consumed by its peer, but the scientists cannot determine if the cannibal tyrannosaur was exhibiting scavenging behavior or was the actual killer.

"Exactly who did the eating that day, in the Late Cretaceous, could still be sorted out by the same grooves," McLain said.

The findings were presented at the 2015 GSA Annual Meeting .