Hundreds of farmers and indigenous Macuxi indians in war paint blocked Amazon roads for a third day, while three Catholic missionaries taken hostage in protest at plans for a new regional indian reserve were released.
Armed, symbolically, with bows and arrows, their faces painted black, the Macuxi said the 1.6 million hectare (3.9 million acre) Raposa Serra do Sol reservation in the north of Amazon state would force them into isolation.
They say it will prevent them from trading the rice they grow.
"We are no longer in the stone age and we believe in integration," said Jonas Marculino, an indigenous farmer and teacher and spokesman for the 200 indians who have occupied the National Indian Foundation (FUNAI) building in Boa Vista, capital of the northern state of Roraima since Tuesday.
"If the reserve is created, we will be isolated and we will not be able to work," Marculino told AFP.
Protests began after the government said the demarcation of borders for the reserve, begun in 1998, should be finished by the end of this month.
Brazil's Justice Minister Marcio Thomas Bastoz was to meet this week with Roraima state governor Flamarion Portela, who also opposes the reserve, saying that at 15,782.74 square kilometers (6,093.75 square miles), approximately half the size of Belgium, it is too big.
The minister is also expected to start negotiating compensation terms with 67 farmers whose land will be appropriated for the reserve, press reports said Thursday.
Since Tuesday, hundreds of Macuxis, backed by the farmers, have blocked main roads and disrupted traffic through Roraima to Venezuela and Guyana to pressurize the government.
Petrol tankers and produce trucks were stuck in the traffic, causing shortages in Boa Vista.
Meanwhile a state lawmaker who supports the protests, Luciano de Castro, warned Governor Portela the protests could close down a regional airport and bus terminals.
However, those opposed to the demonstrations played down its effects.
"It is just a minority of indians who are recruited and manipulated by seven desperate rice producers in the region," said Mercio Gomes, the head of FUNAI.
He said most indigenous people and the Roman Catholic church back the reserve's creation, from which members of other ethnic groups will be banned unless they have FUNAI permission to enter.
Most shops in Boa Vista had also pulled down their shutters in a show of support for the protesters.
The church-linked Indigenous Missionary Council said in a statement that "tension is rising with each passing moment because the great majority of indigenous people have been fighting for the reserve for 30 years."
The three abducted missionaries who had been working at Raposa Serra do Sol were released by the protesters around 5:00 pm (1900 GMT) Thursday, said Boa Vista priest Edson Damian.
Brazilian Ronildo Pinto Franca, Colombian Juan Carlos Martinez and Spaniard Cesar Avellaneda "were very tired, had not been subjected to any kind of violence, but had been ridiculed by the indians," Damian said.
The three were flown by helicopter from Conta to Boa Vista where doctors examined them.
"It was creating international tension, and there was pressure from the Vatican," Marculino said.
"We are not against the reserve. But they should take off 300,000 hectares (740,000 acres) to avoid the compulsory appropriation of the farmers installed in the region," said Marculino.
"Our objective is not violence ... We are waiting for a gesture from Brasilia," he added.
Gomes said, however, that the FUNAI would not change its decision on the size of the reserve. He said that of the 15,000 indigenous people in the region, some 4,000 were opposed to it.
Brazil's population tops 170 million, including some 358,000 indigenous people -- under one percent of the population -- from 215 ethnic groups speaking 180 dialects.