Brazil's environmental agency says it's detained a land-grabber thought to be the Amazon's single biggest deforester.

The Brazilian Institute of Environment and Renewable Natural Resources says Ezequiel Antonio Castanha was detained Saturday in the state of Para.

He's accused of operating a network that illegally seized federal lands, clear-cut them and sold them to cattle grazers.

The agency blames the network for 20 percent of the deforestation in Brazil's Amazon in recent years. Rio de Janeiro's O Globo newspaper estimates Castanha's group clear-cut some 58 square miles (15,000 hectares).

Monday's statement says Castanha will face charges including illegal deforestation and money laundering, and could face up to 46 years in prison.

Officials say about 1,870 square miles (4,848 square kilometers) of forest were destroyed last year.