An indigenous community in the Ecuadorian Amazon has won a reprieve after building up an arsenal of spears, blowpipes, machetes and guns to fend off an expected intrusion by the army and a state-run oil company.

Archaeologists estimate that the items have remained hidden from view inside a cave for nearly 5,000 years.

To slake the overwhelming thirst for electricity of São Paulo and the surrounding metropolis, as well as its growing industry, Brazil is preparing to build the third largest hydroelectric dam in the world on the Xingu River, a major tributary of the Amazon.

MONTREAL—The aboriginal movement known as Idle No More continued to gain strength beyond Canada’s borders on Tuesday as activists embarked on a public relations blitz in the United States.

In what looks set to be one of the most one-sided struggles in the history of Amazon forest conservation, an indigenous community of about 400 villagers is preparing to resist the Ecuadorean army and one of the biggest oil companies in South America.