Scientists have found evidence of the earliest known homicide in a 4,30,000-year-old human skull in Spain. The fossilized skull discovered deep inside a Spanish cave in the Atapuerca mountains belonged to a primitive member of the Neanderthal lineage.

The research was carried out at the archaeological site of the Sima de los Huesos Spanish for 'Pit of the Bones'. The site is located deep within an underground cave system and contains the skeletal remains of at least 28 individuals that lived during the Middle Pleistocene time period.

The murder victim suffered two penetrating fractures on the forehead's left side above the eye. The presence fractures of similar size on the frontal bone strongly suggested right-handed member had stuck the skull during a face- to-face conflict and was killed.

Paleontologist Nohemi Sala of Madrid's Centro Mixto UCM-ISCIII de Evolucion y Comportamiento Humano said, "This individual was killed in an act of lethal interpersonal violence, providing a window into an often-invisible aspect of the social life of our human ancestors. In the fossil record, there are many cases of traumatic injury, but not a lot of evidence of killing".

Sala and her colleagues identify them as members of the species Homo heidelbergensis, an early human ancestor that gave rise to the Neanderthals.

The researchers interpreted the wounds, each nearly an inch (2 cm) wide by using forensic methods like those employed by police. The wounds are the evidence of bluntforce trauma that occurred around the time of death. The body was then dropped down a 43-foot shaft into a cave, where it lay for nearly half a million years.

The skull's forensic analysis was reported Wednesday in the journal PLOS ONE.