SAO PAULO — Brazilian police said Monday they planned to indict a Colombian fish trader as the mastermind of last year’s slayings of Indigenous expert Bruno Pereira and British journalist Dom Phillips.

Ruben Dario da Silva Villar provided the ammunition to kill the pair, made phone calls to the confessed killer before and after the crime, and paid his lawyer, federal police officials said during a press conference held in Manaus.

Fisherman Amarildo da Costa de Oliveira, nicknamed Pelado, confessed that he shot Phillips and Pereira and has been under arrest since soon after the killings in early June. He and three other relatives are accused of participating in the crime. They all live in an impoverished riverine community inside a federal agrarian reform settlement between the city of Atalaia do Norte and Javari Valley Indigenous Territory.

Villar has denied any wrongdoing in the case. Before Monday’s announcement, he was already being held on charges of using false Brazilian and Peruvian documents and leading an illegal fishing scheme. According to the investigation, he financed local fishermen to fish inside Javari Valley Indigenous Territory.

In a statement, UNIVAJA, the local Indigenous association that employed Pereira, said it believed there were other significant planners behind the killings who have not been arrested.

Pereira and Phillips were traveling in the remote area of the Amazon when they disappeared, and their bodies were recovered after the confessions. Phillips was researching for a book about how to save the world’s largest rainforest.