A badger-like mammal died while chomping into the ribs of a hapless horned plant-eating dinosaur struggling to escape more than 100 million years ago. The pair were perfectly preserved, still locked in combat, in “China’s dinosaur Pompeii,” researchers report.

Dating to the Cretaceous Period, the dramatic fossil unearthed in northeastern China shows the four-legged mammal Repenomamus robustus — the size of a domestic cat — ferociously entangled with the beaked two-legged dinosaur Psittacosaurus lujiatunensis, as big as a medium-sized dog.

Scientists suspect they were suddenly engulfed in a volcanic mudflow and buried alive during mortal combat.

“Dinosaurs nearly always outsized their mammal contemporaries, so traditional belief has been that their interactions were unilateral — the bigger dinosaurs always ate the smaller mammals,” said paleobiologist Jordan Mallon of the Canadian Museum of Nature in Ottawa, who helped lead the study published in the journal Scientific Reports.

“Here, we have good evidence for a smaller mammal preying on a larger dinosaur, which is not something we would have guessed without this fossil,” Mallon said.