RIO DE JANEIRO, Brazil (AP):

Deep in the northernmost reaches of the Amazon jungle, a land conflict between rice farmers and a handful of Indian tribes has turned so violent that the country's Supreme Court warns it could escalate into civil war.

The court is expected to decide in August if the Government can keep evicting rice farmers from a 4.2- million acre (1.7 million hectare) Indian reservation decreed by President Luiz Inacio Lula da Silva in 2005. The evictions were stopped in April when rice farmers started burning bridges and blockading roads, and justices said they feared a "veritable civil war.''

Important decision

The court's decision could help determine the future of the Amazon, whose remaining jungles provide a critical cushion against global warming. It could also redefine Brazil's policy toward its Indians at a time of frequent confrontations, as the country spends billions of dollars opening roads, building dams and promoting agribusiness across the world's largest remaining tropical wilderness.

Unlike most other Latin American countries, where indigenous people are fighting for rights in mainstream society, most of Brazil's Indians continue to live in the jungle and maintain their languages and traditions. These Indians have fought for decades to keep or regain their ancestral lands.

Increasing conflict

Brazil's 1988 constitution declared that all Indian ancestral lands must be demarcated and turned over to tribes within five years. While that process has yet to be completed, today, about 11 per cent of Brazilian territory and nearly 22 per cent of the Amazon is in Indian hands.

But as logging, ranching and farming expand into the Amazon, there has been increasing conflict with the Indians and pressure on the government to limit the size of reservations.

Earlier this summer, government anthropologists revealed photos of one of the world's last uncontacted tribes fleeing logging near the Peruvian border.

In May, Indians protesting a proposed hydroelectric dam on the Xingu River in Para state machete-slashed a government official who came to speak to the group.