Illegal logging and clearing of Brazil's Amazon rainforest increased 16 percent in the last year, the government said, in a setback to the aim of stopping destruction of the world's greatest forest by 2030.
The area of deforestation grew to 2,251 square miles (5,830 square kilometers) between July 2014 and August 2015, the environment ministry said.
The biggest increases were in the states of Amazonas, with a 54 percent rise, Rondonia with 41 percent and Mato Grosso with 40 percent, the ministry said.
The sharp deterioration came despite Brazil's attempts to increase policing of the rainforest, which is seen as a key element in the fight to keep greenhouse gases under control—the subject of a major climate change summit starting in Paris on Monday.
"We have to investigate what is happening," said Environment Minister Izabella Teixeira. "We will ask the states to tell us formally what was authorized and what was illegal."
Preliminary reports suggest that expansion of cattle ranching and agriculture is to blame for the clearances.
The Amazon is a giant trap for carbon that would otherwise be released, contributing to global warming. It is also one of the world's greatest remaining sanctuaries for rare and often still barely studied flora and fauna.
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