The Brazilian government says it can't locate the members of a small tribe in the Amazon rainforest.

The tribe has been documented in aerial photos in 2008 and 2011. Its members have largely remained isolated from non-Indians for centuries.

But the National Indian Foundation, Brazil's Indian affairs agency, says suspected drug traffickers from Peru appear to have chased the tribe away. The outsiders were armed with sub-machine guns and rifles, according to the government.

Some traces of the tribe, including an arrowhead, have been found. A government official fears the tribe may have been massacred and referred to the situation as "genocide," the Associated Press reported.

Get the Story:
Did Drug Violence Eliminate an 'Uncontacted' Amazon Tribe? (Time 8/10)
Brazil fears drug traffickers may have entered land occupied by isolated Indians (AP 8/9)
Remote Brazilian tribe threatened by 'drug dealers (BBC 8/8)

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NYT Blog: Brazil releases photos of an isolated tribe in the Amazon (2/3)