During an arduous six-hour hike through dense forest, the Uru Eu Wau Wau waded through water and clouds of buzzing insects to reach a large stretch of land that had recently been reduced to ashes.

The Uru Eu Wau Wau could do little more than take photos of the damage and then set fire to the small encampment.

When asked about what the Bolsonaro administration’s policies may do to communities like these, Ms. Cardozo, who has supported the tribe for decades, looked dejected.

“Their objective is to force them from their lands and turn them into ordinary citizens in the periphery of cities, into beggars,” she said. “To me that amounts to a policy of genocide and ethnocide.”

One of the oldest members of the tribe, Borea Uru Eu Wau Wau, has scars on her back from bullet wounds she suffered during an ambush by rubber trappers in the 1980s. A sister, aunt and grandmother were killed then, she recalled.

Since the new wave of incursions began, Borea has experienced flashbacks, which have left her with a fatalistic view about the future.

“It takes too long to wait for justice, for which we’ve waited and waited,” she said, speaking barely above a whisper. “It’s easier to kill.”