An aerial picture released by Greenpeace shows forest fires in the indigenous lands in Arariboia, Maranhao state, North of Brazil, on October 24, 2015

A fire that for more than a month has ravaged a region in northeast Brazil inhabited by an isolated Native American tribe has finally been contained, the authorities said.

Luciano Evaristo, a local director of the Brazilian Institute of Environment and Renewable Natural Resources, said Friday that had extinguished 90 percent of the fires in Maranhao state, on the edge of the Amazon jungle, with an additional 10 percent now under control.

The destruction has been extensive in the Arariboia Indigenous Reserve, amounting to more than half its 413,000 hectares (1 million acres), or the rough equivalent of 190,000 football fields.

A number of the 12,000 ethnic Guajarara natives who live in the reserve lost their homes, Evaristo said. But the 80 or so members of the tiny Awa-Guaja tribe, who live deep in the forest cut off from the outside world, were unaffected.

Greenpeace, which has been monitoring the blaze, confirmed to AFP that the was contained but said that it was "impossible to be sure that it was completely extinguished."

More than 300 firefighters and soldiers have battled the blaze along a fiery frontline more than 100 kilometers long (60 miles) since September 24.

The indigenous people have said the fire was "of criminal origin," blaming it on clandestine timber-cutting operations. They say the blaze was in retaliation for efforts by the natives to step up surveillance to prevent the illegal deforestation of their lands, according to Greenpeace.

"They are burning our forest, and it's a crime against my people and against the isolated peoples but also against the biodiversity of the Earth," an Arariboia leader, Olimpio Guajajara, told Greenpeace a few days ago.

On Friday, the Brazilian environmental institute confirmed that the fire had been started by clandestine woodcutters and said that they would be expelled from the forest.

Some 900,000 natives of 305 ethnic groups live in Brazil, a country with a total population of 204 million. Their lands occupy 12 percent of the national territory, most of it in the Amazon, but settlers and others have made serious encroachments.