Brazilian police say a suspect has confessed to shooting British journalist Dom Phillips and indigenous expert Bruno Pereira.
Detective Eduardo Fontes said the man, Amarildoda Costa de Oliveira, took investigators to a site where human remains were dug up.
He said police would work with Interpol to confirm the bodies’ identities.
Two suspects, Amarildo and Oseney da Costa de Oliveira, have been arrested so far. They are reportedly brothers.
Police said they expect to carry out further arrests.
Mr Phillips, 57, and Mr Pereira, 41, went missing in a remote part of the Amazon rainforest on 5 June.
Briton Mr Phillips had been living in Brazil for more than a decade and was a long-time contributor to the Guardian newspaper. He was working on a book about the Amazon.
Mr Pereira, a Brazilian who was on leave from his post with the government’s indigenous affairs agency Funai, was an expert on isolated tribes.
Some of their belongings, including clothes and a laptop, were found on Sunday.
It was a hastily-organised press conference – after another day of rumours that the bodies had been found.
The federal police officer in charge of the investigation showed a map to the waiting media – explaining that the bodies were found 3.1km (1.9 miles) from the river, in the middle of the jungle – and that involved a huge amount of work to get to the location that the suspect had indicated.
There was a great deal of praise for the joined-up efforts of all the armed forces – patting themselves on the back after a huge amount of criticism at the start that they hadn’t mobilised quickly enough.
They also initially failed to praise the work of the indigenous communities who have been out searching since the men disappeared, and helped lead authorities to some of the their belongings found in the water. When asked by the BBC why there was no mention of the local communities helping, they admitted their support in working with the armed forces, with the head of the army in Amazonas explaining that many troops are indigenous in the force and that was crucial.
It might sound like a minor omission, but it reveals the divide between the bosses at the top here in the city – and the people living in these remote, difficult places.
Days before Mr Phillips and Mr Pereira went missing, indigenous groups say Mr Pereira was threatened for campaigning against illegal fishing in the area.
Mr Phillips’ sister, Sian, previously told the BBC: “I think it’s likely they’ve been ambushed by some illegal criminal activity there, possibly to do with illegal fishing.”
It is an “incredibly distressing and awful situation”, she said.
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