The Inter-American Commission on Human Rights (IACHR, or CIDH in Spanish), a body of the Organization of American States (OAS), issued a statement Sept. 5 urging Venezuelan authorities "to conduct a thorough investigation" into assertions made by representatives of the Horonami Yanomami organization that an isolated Yanomami  community in southern Amazonas state was massacred by outlaw gold-miners who came across the Brazilian border. The statement came days after Venezuela's Minister for Indigenous People Nicia Maldonado and Justice Minister Tareck el Aissami both said that teams sent to the region had found no evidence of a massacre. The IACHR called on both Venezuela and Brazil to pursue a deeper investigation, and report back their findings to the international body.

Venezuelan officials investigating a reported mass killing of Yanomami indigenous people say the have found no evidence of the attack. Minister of Indigenous Peoples Nicia Maldonado said a team travelled to the area by helicopter and failed to locate the bodies witnesses had described finding. "No evidence of any death was found," Maldonado said on state TV. "There is no evidence of murder or fire in either houses or shabonos [communal dwellings] in the communities where the alleged crime took place." Gen. José Eliecer Pinto of the National Guard told Ultimas Noticias newspaper that he had visited four indigenous communities along with other officials and that "everything is fine there." Officials expressed skepticism at claims that outlaw gold miners came across the border from Brazil to attack the settlemet from the air by helicopter.  "It would be extremely hard to do," said Gen. Rafael Zambrano, commander of the Venezuelan army unit responsible for the region.

A Brazilian federal judge in Pará on Aug. 31 agreed to conduct the first trial against members of the former dictatorship for alleged crimes during the military's rule from 1964-1985. The defendants are two retired army reserve members, Col. Sebastiao de Moura and Maj. Licio Maciel, accused of kidnappings during suppression of the guerilla movement in the Araguaia region between 1972 and 1975. The judge agreed with prosecutors that Brazil's 1979 amnesty law, which provides amnesty for members of the government and military alleged to have committed political crimes between 1961 and 1975, does not apply because bodies of the alleged kidnapping victims were never found, and the cases are therefore still technically open.

Amnesty International reports that 45 families from the Quilombo Pontes community in Pirapemas municipality, in Brazil's northeastern Maranhão state, are being systematically threatened and intimidated by gunmen who are patrolling the area. The gunmen are employed by local ranchers who are trying to push the community off the land. Crops and property belonging to the community have been destroyed, and its members are now struggling to provide food for their families. The Pontes community was officially recognised as a quilombo territory—communities of descendants of escaped slaves—in December 2011, but the authorities have not intervened to guarantee the integrity of their land.

Authorities in Venezuela pledge to investigate breaking reports that illegal gold miners in southern Amazonas state carried out a "massacre" of an isolated Yanomami indigenous community. Witnesses of the aftermath described finding "burnt bodies and bones" at the community of Irotatheri, Alto Orinoco municipality, near the Brazilian border in the headwaters of the Río Ocamo, an Orinoco tributary. (See iTouch Map; Venezuela political map) Blame is being placed on illegal miners, known as garimpeiros, who cross the border from Brazil to prospect for gold and have attacked indigenous peoples before.

A Brazilian federal judge on Aug. 23 ruled that permits for more than 120 proposed hydro-electric dams in the Upper Paraguay River Basin cannot be issued without first conducting environmental impact assessments, dealing a blow to a major thrust of development planned for the states of Mato Grosso and Mato Grosso do Sul. The ruling comes in response to a request from state and federal prosecutors in Mato Grosso do Sul, who petitioned the 1st Federal Court in Coxim for an injunction suspending construction of 126 new dams in the Pantanal, a vast region of wetlands in the basin. The ruling also impacts 20 already operating hydro plants, which will be able to continue running under their current licenses, but must submit to an impact study before seeking license renewals. Utilities must seek approval for the studies from the Brazilian Institute for the Environment and Natural Resources (IBAMA) as well as state authorities before the projects can move ahead.

Brazil's Supreme Court on Aug. 22 ordered the release of Amazon rancher Regivaldo Galvão, convicted in the 2005 killing of US nun and rainforest activist Dorothy Stang. In 2010, Galvão was convicted by a court in Belém, Pará state, of ordering Stang's death, and sentenced to 30 years. The following year, the Pará court ordered that he start serving his term immediately, even while pursuing an appeal of his conviction. But the Supreme Court ruled that Galvão had the right to remain free pending the outcome of his appeal.

A group of judges from Brazil's Regional Federal Tribunal (TRF1) suspended construction of the Belo Monte dam project on the Amazon's Xingu River Aug. 14, finding that indigenous people had not been properly consulted prior to approval of the project. The ruling upheld an earlier decision that declared the Brazilian Congress' authorization of the project in 2005 to be unconstitutional. The decision finds that the Brazilian constitution and ILO Convention 169, to which Brazil is party, require that Congress can only authorize the use of water resources for hydroelectric projects after an independent assessment of environmental impacts and subsequent consultations with affected indigenous peoples.