The outside world may change at a dizzying speed, but these people live largely as they have done for 20,000 years.

Extraordinary photographs taken from a helicopter flying over the Amazonian jungle show members of one of the world’s last ‘uncontacted’ tribespeople.

The Indians exist in isolated nomadic groups in the depths of the Brazilian rainforest near the Peruvian border.

When the helicopter first appeared low overhead earlier this month, they were panic-stricken — fleeing from their thatched shelters in a clearing to hide under the foliage.

Then the men took courage and fired volleys of primitive arrows at the noisy interloper.

The meeting of shy Neolithic man and his inquisitive 21st-century counterpart was pure chance. Photographer Ricardo Stuckert was on his way to meet another tribe — which already has contact with modern man — in the north-western state of Acre.

But a thunderstorm forced his helicopter to divert — and he spotted these Indians. A second fly-past yielded more images.

It is thought the men are from the same unnamed tribe observed from the air in 2008 and 2010. They are believed to have moved on a number of occasions since then.

‘To think that in the 21st century, there are still people who have no contact with civilisation, living like their ancestors did 20,000 years ago — it’s a powerful emotion,’ Stuckert told National Geographic magazine.

‘They seemed more inquisitive than fearful. There was a mutual curiosity, on their part and mine. I felt like I was a painter in the last century.’

The pictures show the tribesmen wearing very little save bright red body paint — which he assumed is camouflage. A colourful macaw parrot can be seen perched on a roof.