The lost tribe staring extinction in the face: Extraordinary new pictures of life in the depths of the Amazon jungle

Lost tribe: Bow and arrow at the ready, and with faces contorted with curiosity, the group stare and point at the unknown object hovering in the sky

These incredibly detailed photographs offer a unique insight into the lives of one of the world's last uncontacted tribes. Spears aloft, faces daubed with vivid red paint these bewildered villagers stare up at the helicopter high above them. For them, as for those who saw them, it was a remarkable moment as the group live in total isolation in the dense Amazon rainforest along the Brazilian-Peruvian border. The aerial images were taken by Brazilian authorities, who have been monitoring the group for some time, and - concerned about their welfare - they have handed them to British charity Survival International, and other NGOs, in the hope that they can help protect their territory and preserve their isolated existence.

Fears are growing that an influx of illegal loggers from Peru could threaten their survival, by pushing back other tribes in the River Envira area and creating bloody conflict over raw materials and land. Three years ago Survival International released images of the same tribe to prove their existence and the fact that they should be protected from the loggers, who were scything their way though the rainforest. On that occasion the hunters of the group fired arrows and flung spears at the helicopter, not knowing - of course - what the helicopter was.

Mrs Watson, who has worked for Survival for 20 years, is fearful that if pressure is not put on the Peruvian government to expel the loggers, then this small cluster of tribes - and their fascinating way of life - will be lost for ever.

'I'm extremely angry and I don't understand why in our world today a lot of people don't think that these groups don't have as much rights as anyone else,' [she told MailOnline.] 'They are a fantastic example of how to live a sustainable life. They are very sophisticated and no one has a better understanding of their environment. We can learn a lot from them. 'What we are seeing is people who are living differently but they are human beings like you or me. There is a moral and ethical issue. What right do we have to tell them how to live?