LONDON (AP) — Scientists in Britain say ancient humans may have learned to make fire far earlier than previously believed, after uncovering evidence that deliberate fire-setting took place in what is now eastern England around 400,000 years ago.

The findings, described in the journal Nature, push back the earliest known date for controlled fire-making by roughly 350,000 years. Until now, the oldest confirmed evidence had come from Neanderthal sites in what is now northern France dating to about 50,000 years ago.

The discovery was made at Barnham, a Paleolithic site in Suffolk that has been excavated for decades. A team led by the British Museum identified a patch of baked clay, flint hand axes fractured by intense heat and two fragments of iron pyrite, a mineral that produces sparks when struck against flint.

Researchers spent four years analyzing to rule out natural wildfires. Geochemical tests showed temperatures had exceeded 700 degrees Celsius (1,292 Fahrenheit), with evidence of repeated burning in the same location.

That pattern, they say, is consistent with a constructed hearth rather than a lightning strike.

Rob Davis, a Paleolithic archaeologist at the British Museum, said the combination of high temperatures, controlled burning and pyrite fragments shows “how they were actually making the fire and the fact they were making it.”

Iron pyrite does not occur naturally at Barnham. Its presence suggests the people who lived there deliberately collected it because they understood its properties and could use it to ignite tinder.

Deliberate fire-making is rarely preserved in the archaeological record. Ash is easily dispersed, charcoal decays and heat-altered sediments can be eroded.

At Barnham, however, the burned deposits were sealed within ancient pond sediments, allowing scientists to reconstruct how early people used the site.

Researchers say the implications for human evolution are substantial.

Fire allowed early populations to survive colder environments, deter predators and cook food. Cooking breaks down toxins in roots and tubers and kills pathogens in meat, improving digestion and releasing more energy to support larger brains.

Chris Stringer, a human evolution specialist at the Natural History Museum, said fossils from Britain and Spain suggest the inhabitants of Barnham were early Neanderthals whose cranial features and DNA point to growing cognitive and technological sophistication.

Fire also enabled new forms of social life. Evening gatherings around a hearth would have provided time for planning, storytelling and strengthening group relationships, which are behaviors often associated with the development of language and more organized societies.

Archaeologists say the Barnham site fits a wider pattern across Britain and continental Europe between 500,000 and 400,000 years ago, when brain size in early humans began to approach modern levels and when evidence for increasingly complex behavior becomes more visible.

Nick Ashton, curator of Paleolithic collections at the British Museum, described it as “the most exciting discovery of my long 40-year career."

For archaeologists, the find helps address a long-standing question: When humans stopped relying on lightning strikes and wildfires and instead learned to create flame wherever and whenever they needed it.