Human remains from a cave in northern Spain show evidence of a lethal attack 430,000 years ago, a study has shown.

Researchers examined one skull from a site called the Pit of Bones, which contains the remains of at least 28 people.

They concluded that two fractures on that skull were likely to have been caused by “multiple blows” and imply “an intention to kill”.

The findings are published in the journal PLOS One.

As well as providing a clue as to why the bodies were in the cave, scientists say the study provides grisly evidence that violence is an intrinsic part of the earliest human culture.

The international research team studied the skull – cranium 17 – using modern medical imaging techniques.

Their virtual reconstruction showed that two clearly visible fractures on its front were almost identical, strongly suggesting, “that both were caused by the same object”.

Lead researcher Dr Nohemi Sala from the Salud Carlos III Institute in Madrid told BBC News: “This individual was killed in an act of lethal interpersonal violence.

“[This is] a window into an often invisible aspect of the social life of our human ancestors.”

The forensic investigation of this ancient death provides a piece in the puzzle of how these people came to be in the cave, which is known in Spanish as Sima de los Huesos.