An isolated Amazon tribe's first contact with modern civilization is revealed in footage released by the Brazilian government this week.

The eight-minute video posted Thursday on YouTube by Brazil's National Indian Foundation, Funai, was filmed on the second day of a Funai team's contact with the group, on June 30, reported Agence France-Presse. Seven members of the tribe made contact with a "settled" indigenous Ashanika community near the Envira River in Brazil's Acre state, near the border with Peru.

The video shows a group of young, mostly naked men being approached by boat as they talk and sing. In one scene, they hold bows and arrows during what appears to be a peaceful meeting with a group of Brazilian men dressed in T-shirts, pants and baseball caps. In another, they accept a bunch of bananas while wading in the middle of the Envira River. The final scene shows two men from the tribe walking away from the camera carrying a modern axe and a machete as the person filming shouts at them.

Uncontacted tribe Indians Amazon

The group returned to its village, but later had to come back to be treated for influenza. People from isolated tribes have little immunity to contagious diseases. (Funai/Reuters)

The previously uncontacted tribe, with members speaking a language that's part of the known Panoan linguistic group, first made contact on June 26.

According to a Funai news release, the group reported it had been violently attacked by non-Indians at the headwaters of the Envira River in neighbouring Peru. The non-profit group Survival International, which advocates for uncontacted tribes, said Brazilian experts believe the attacks may have been related to illegal logging and drug trafficking.

The people from the newly contacted tribe later returned to their rainforest village, but all seven of them contracted influenza as a result of the contact they made with outsiders – many isolated tribes have little immunity to contagious diseases and in the past, contact with the modern world has sometimes led to deadly disease epidemics.

In a statement released July 17, Funai said members were moved to a government facility and given medical care, then returned to the villages.

Stephen Cory, director of Survival International, said in a statement that the incident was "a real test of Brazil's ability to protect these vulnerable groups" and that a sustained medical program was needed or "the result could be a humanitarian catastrophe."

According to Funai and Survival International, there are thought to be more than 70 uncontacted tribes in the Amazon that have chosen not to be in contact with modern civilization.

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