The air force said it was deploying fighter jets and surveillance planes to wrest back control of the airspace over the remote Amazon rainforest territory and halt movement of small aircraft that resupply the outlaw mining camps.

Indigenous leaders say some 20,000 miners have set up illegal operations, raping and killing inhabitants, poisoning their water with mercury and ravaging the forest they depend on for food.

Police opened an investigation last week into crimes including genocide on the reservation, after images of starving Yanomami children shocked the world.

President Luiz Inacio Lula da Silva issued an order Monday closing the airspace over parts of the region and authorizing the military to divert planes suspected of resupplying illegal camps.

"The problem has a cause, and we know what it is: illegal gold mining. It will be eradicated. We're going in ready to take them on," Defense Minister Jose Mucio said Tuesday.

"All suspect flights will be diverted and the planes forced to land for identification."

The government has reported around 100 Yanomami children died of malnutrition and other diseases last year.

Mucio said he would visit the territory Wednesday next week with the commanders of the army, air force, navy and federal police.

The air force says it has already flown 61 tons of food and medical supplies into Yanomami territory since last week, and set up a field hospital to treat Indigenous patients in Boa Vista, the capital of Roraima state.

The head of the field hospital, Juliana Freire Vandesteen, told a news conference medical personnel had treated 300 people so far, mostly children.

"There are a lot of cases of pneumonia, intestinal parasites, malaria and skin diseases," she said.

The Yanomami territory, the largest reservation in Brazil, sits on the country's northern border with Venezuela. It spans 96,000 square kilometers (37,000 square miles) and is home to around 30,000 Indigenous inhabitants.

Illegal gold mining rose sharply in Brazil under far-right former president Jair Bolsonaro (2019-2022), who pushed to open protected Indigenous reservations to mining and presided over a surge of destruction in the Amazon.

A Supreme Court judge on Monday ordered authorities to extend their genocide investigation to former officials in Bolsonaro's government.