Dom Phillips (left) and Bruno Pereira disappeared during a trip to a remote part of the Brazilian Amazon in June.
CNN  — 

Authorities in Brazil have charged three men with “aggravated double homicide and concealment of a corpse” following the disappearance last month of British journalist Dom Philips and Brazilian indigenous expert Bruno Pereira.

Amarildo da Cosa Oliveira, Oseney da Costa de Oliveira, and Jefferson da Silva Lima were processed as defendants for the crimes committed in the Javari Valley, according to a statement released by the federal prosecutor’s office Friday.

Veteran journalist Phillips and indigenous expert Pereira vanished on June 5 during a trip to the far western part of Amazonas state. Their deaths in the remote region have drawn global attention to the perils often faced by journalists and environmental activists in Brazil.

A federal court judge in Amazonas lifted the confidentiality surrounding the case’s details on Thursday.

Amarildo and Jefferson allegedly confessed to the crime in June and Amarildo led authorities to the bodies. However, Oseney’s participation was established through witness statements, according to the federal prosecutor’s office.

“There were already records of disagreements between Bruno and Amarildo over illegal fishing in the indigenous territory,” the statement said.

“What motivated the murders was the fact that Bruno had asked Dom to photograph the boat of the accused,” it alleged.

Pereira was implied to have been the target of the crime, while Philips “was murdered just for being with Bruno,” in order “to ensure impunity for the previous crime,” the statement said.

Phillips and Pereira were conducting research for a book project on conservation efforts in the region, which authorities have described as “complicated” and “dangerous,” and known to harbor illegal miners, loggers, and international drug dealers.

They were last seen in the Sao Rafael community, a two-hour boat ride from Atalaia do Norte city, after accompanying an indigenous patrol in the Itaquaí river organized to prevent invasions from illegal fisherman and hunters on the Javari Valley Indigenous Land.

They had reportedly received death threats just days prior to their disappearance.

Between 2009 and 2019, more than 300 people were killed in Brazil amid land and resource conflicts in the Amazon, according to Human Rights Watch, citing figures from the Pastoral Land Commission, a non-profit affiliated with the Catholic Church.

And in 2020, Global Witness ranked Brazil the fourth most-dangerous country for environmental activism, based on documented killings of environmental defenders. Nearly three quarters of such attacks in Brazil took place in the Amazon region, it said.

CNN’s Camilo Rocha, Rodrigo Pedroso and Philip Wang contributed reporting.