(CNN) -- In an effort to ramp up pressure for Peru to crack down on illegal loggers in its region of the Amazon, an indigenous rights organization has released what it says are photos of an uncontacted tribe in Brazil that is threatened by the logging across the border.

Survival International says the previously unpublished aerial photos, which it released Monday, show members of an uncontacted Brazilian tribe that is likely to get drawn into conflicts with Peruvian tribes who are fleeing their homes because of the logging.

One photo shows five tribe members, some in red tribal paint, standing in front of a hut and looking upward. One man is holding a bow, and another, younger person, holds a machete. Foods including bananas, papayas and cassava can be identified near the tribe members.

The photos were taken by Brazil's National Indian Foundation and were given to Survival International, it said.

"The illegal loggers will destroy this tribe," Survival International Director Stephen Corry said in a written statement. "It's vital that the Peruvian government stop them before time runs out. The people in these photos are self-evidently healthy and thriving. What they need from us is their territory protected, so that they can make their own choices about their future."

More than 100 uncontacted tribes remain worldwide, and about half live in the remote reaches of the Amazonian rainforest in Peru or Brazil, near the recently photographed tribe, the organization says.

"But this area is now at real risk, and if the wave of illegal logging isn't stopped fast, their future will be taken out of their hands. This isn't just a possibility: it's irrefutable history, rewritten on the graves of countless tribes for the last five centuries," Corry said.

Loggers in Peru are pushing isolated Indians from Peru into Brazil, where, according to Survival International, "the two groups are likely to come into conflict."

Several nongovernmental organizations have pushed Peru to act against the logging for years, but little has been done, they say.