Officials still haven't been able to locate the tribe, CNN says, and cannot say whether the Indians were run off by a group of suspected drug traffickers.
Brazil's National Indian Foundation conducted an overnight flight of the tribe's huts, but did not spot anyone. When the agency flew over the area in the past, villagers appeared frightened and armed themselves with longbows.
The huts and crops were still there and appeared untouched, agency spokesman Bruno Perez told CNN.
The aid group Survival International reported this week that suspected drug traffickers attacked a government-run guard post near the tribe's lands. There has been no sign of tribe members since the attack.
It is the policy of the Brazilian government not to contact tribes that still are isolated from the outside world.
More from Que Pasa: Photos of the missing tribe