Up to 3,000 timber companies in Brazil’s Para state are allegedly involved in a scheme that passes illegal wood off as eco-certified product, according to the country’s O Globo newspaper.

Federal prosecutors are reportedly investigating the matter, which apparently involves wood being exported to world markets, including Europe.

The investigation is examining evidence that companies are doctoring paperwork to disguise the source of the wood.

Para has the highest deforestation rate in the Brazilian Amazon region.