The government said the name of the tribe was not known but the warriors were strong and healthy.
One of South America’s few remaining uncontacted indigenous tribes has been spotted and photographed on the border between Brazil and Peru.
The Brazilian government says it took the images to prove the tribe exists and help protect its land.
The pictures, taken from an aeroplane, show red-painted tribe members brandishing bows and arrows.
More than half the world’s 100 uncontacted tribes live in Brazil or Peru, Survival International says.
Stephen Corry, the director of the group – which supports tribal people around the world – said such tribes would “soon be made extinct” if their land was not protected.
Survival International says that although this particular group is increasing in number, others in the area are at risk from illegal logging.