Backed by military aircraft, Brazilian troops on Saturday prepared to deploy in the Amazon rainforest to fight fires that have swept the region and prompted anti-government protests as well as an international outcry.

Some 44,000 troops will be available for "unprecedented" operations to put out the fires, and forces are heading to six Brazilian states that asked for federal help to contain the blazes, Defense Minister Fernando Azevedo said. The states are Roraima, Rondonia, Tocantins, Para, Acre and Mato Grosso.

The military's first mission will be the deployment of 700 troops to the area around Porto Velho, capital of Rondonia, Azevedo said. He added that the military will use two C-130 Hercules aircraft capable of dumping up to 3,170 gallons of water on fires.

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An Associated Press journalist flying over the Porto Velho region Saturday morning reported hazy conditions and low visibility. On Friday, the reporter saw many already deforested areas that were burned, apparently by people clearing farmland, as well as a large column of smoke billowing from one fire.

The Brazilian military operations came after widespread criticism of President Jair Bolsonaro's handling of the crisis. The president Friday authorized the armed forces to get involved in putting out the fires, saying he is committed to protecting the Amazon region.

"It shows the concern of Bolsonaro's government about this issue," Azevedo said. "It was a very fast response."

The defense minister noted U.S. President Trump's offer in a tweet to help Brazil fight the fires, and said there had been no further contact on the matter. Bolsonaro has previously described rainforest protections as an obstacle to Brazil's economic development, sparring with critics who say the Amazon absorbs vast amounts of greenhouse gasses and is crucial for efforts to contain climate change.

The Amazon fires have become a global issue, escalating tensions between Brazil and European countries who believe Bolsonaro has neglected commitments to protect biodiversity. Protesters gathered outside Brazilian diplomatic missions in European and Latin American cities Friday, and demonstrators also marched in Brazil.

Conservationist Paul Rosolie told "CBS This Morning" that military action isn't enough and said the Amazon is at risk of "collapsing."

"The Amazon is a loop. It's producing the moisture that creates all that rain that makes it a rainforest," said Rosolie, who wrote about his experiences in the jungle in his 2014 book, "Mother of God."

"As we chop more of the rainforest down – and this has been going on for decades, this is not an isolated issue — as we chop more of the rainforest, what we're risking is reaching a tipping point, where that moisture system might be too dry to produce the rain. And then you have a serious problem on your hands, because you're talking about the entire Amazon sort of collapsing."

The dispute spilled into the economic arena when French President Emmanuel Macron threatened to block a European Union trade deal with Brazil and several other South American countries. He wants G-7 leaders meeting at a summit in France this weekend to discuss the Amazon crisis.

"First, we need to help Brazil and other countries put out these fires," Macron said Saturday.

The goal is to "preserve this forest that we all need because it is a treasure of our biodiversity and our climate thanks to the oxygen that it emits and thanks to the carbon it absorbs," he said.

Bolivia and Paraguay have also struggled to contain fires that swept through woods and fields, in many cases set to clear land for farming. A U.S.-based aircraft, the B747-400 SuperTanker, is flying over devastated areas in Bolivia to help put out the fires and protect forests.

Fires are common in Brazil in the annual dry season, but they are much more widespread this year. Brazilian state experts reported nearly 77,000 wildfires across the country so far this year, up 85% over the same period in 2018.