Human Rights Watch has accused Brazil's President Jair Bolsonaro of giving a "green light" to illegal loggers to destroy the Amazon and failing to protect those defending the world's largest rain forest.

Bolsonaro, whose anti-environment rhetoric and policies have been widely blamed for a spike in fires and land clearing in the Amazon this year, has promised to open up the remote region to more development even as he faces growing international criticism.

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Amazon deforestation doubled

Official figures show Amazon deforestation nearly doubled in the first eight months of this year, compared with the same period in 2018, to 6,404 square kilometres (2,472 square miles) -- more than twice the size of Luxembourg. 

The acceleration in deforestation has been blamed for the sharp increase in fires this year, which official figures show have reached nearly 124,000, as land is cleared and burned to make way for cattle grazing or crops. 

A decrease in precipitation and a recent heatwave together with strong winds are also factors in the blazes. 

"Through his words and actions, President Jair Bolsonaro has effectively given a green light to criminal groups that are destroying the Amazon and he has put defenders of the forest at serious risk," said Daniel Wilkinson, managing director of HRW's Americas division, at the Sao Paulo launch of a report on illegal logging in the Amazon on Tuesday.

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Criminal networks operate the deforestation process

Criminal networks can coordinate the extraction, processing and sale of timber "on a large scale," and employ gunmen to intimidate or even execute those trying to stop them, the report said. 

Brazil is one of the deadliest countries in the world for land and environmental activists. 

It ranked fourth in 2018 with 20 deaths, Global Witness said in July. "Those responsible for the violence are rarely brought to justice," said the HRW report. In many cases, reports of death threats are not even investigated by police. 

READ | Brazil President Jair Bolsonaro to skip Amazon wildfire summit

Far-right Bolsonaro, who was released from hospital Monday after another operation on his stomach following his stabbing at a campaign rally last year, has rejected Europe-led criticism of his environmental policies. 

He is expected to address the UN General Assembly next week on the huge fires in the Amazon.

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