Video from 2014.
"Engravings on a human bone from a prehistoric archaeological site in a cave in southern England shows that human cannibals ate their prey and then performed ritualistic burials with the remains, scientists said on Wednesday (Aug. 9, 2017)." Source: Thomson Reuters Foundation (2017).
"The forearm bone appears to have been disarticulated, filleted, chewed, and then engraved with a zig-zag design before being broken to extract bone marrow, said scientists from Britain's Natural History Museum who conducted the analysis."
Note: The bones were found in "Gough's Cave [Somerset, England], thought to be from Britain's Palaeolithic period ..." The fact that some kind of cannibalism, possibly ritualistic, was practiced in the cave has been known for some time.
Video from 2009.