Archaeologists have uncovered evidence in northern Kenya of what could be the earliest example of warfare between different human communities, the BBC reports.
The 10,000-year-old remains of 27 people found at a remote site west of Lake Turkana show that they met violent deaths.
They were left to die there rather than being buried.
Many experts had thought conflict emerged only around 6,000 years ago after humans became more settled.
The archaeologists, who have been working on the site at Nataruk since 2012, discovered that the victims were clubbed or stabbed to death in a single event.
The dead included male and female adults, as well as children.
The evidence, published in the journal Nature, does not reveal exactly what happened but it was definitely the result of “some sort of conflict”, according to Cambridge University Professor Robert Foley.