A Ph.D. student, Tanner Harvey studying snake venom at the University of Northern Colorado. filmed very rare video of Male Leopard cannibalizing another Leopard at Serengeti National Park, Tanzania. According to Nat Geo, it is very rare case of Leopard preying other Leopard but sightings go back decades. Leopard after feeding for 90 minutes, it walked to nearby cave.
See embedded video below from Nat Geo:
Source: National Geographic