Brazilian police have arrested a second suspect as they probe the disappearance of journalist Dom Phillips and indigenous expert Bruno Pereira.

Oseney da Costa de Oliveira was detained on suspicion he was involved in the case with his brother, Amarildo da Costa de Oliveira, local media report.

Amarildo earlier denied any wrongdoing.

Mr. Phillips, 57, and Mr Pereira, 41, went missing in a remote part of the Amazon rainforest on 5 June.

Some of their belongings, including clothes and a laptop, were found on Sunday.

In a statement, federal police said they had seized ammunition and an oar in the village of Sao Gabriel, where the two men were last seen. The items have been taken for forensic analysis.

Alex Perez, a police investigator, said Oseney da Costa de Oliveira “did not resist arrest on suspicion of homicide, based on witness accounts that placed the two suspects at the supposed scene of the crime”.

A spokesperson for the indigenous group Univaja, which has been searching for the missing men, said the effort was nearing an end as the area left to examine was getting smaller.

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.

Days before the pair went missing; indigenous groups say Mr. Pereira was threatened for campaigning against illegal fishing in the area.

Speaking to the BBC earlier this week, Mr. Phillips' sister, Sian, said: “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 added.

Ambassador apologises to families

On Monday, Mr Phillips' brother-in-law told the BBC that the Brazilian embassy in the UK had informed the family that two bodies had been found tied to a tree.

Later that day, Brazilian police denied the report and said they had only found belongings and “biological material”, which would be tested.

The Brazilian ambassador in the UK has now apologised to Mr Phillips' family for the miscommunication, Reuters reports.

Ambassador Fred Arruda said the information had come from investigating officials in Brazil, adding: “I wholeheartedly apologise.”

In Brazil's capital, Brasilia, indigenous protesters carried banners emblazoned with the missing men's faces to the Ministry of Justice on Tuesday, calling for justice. (BBC)

•PHOTO: Brazilian soldiers have been looking for the missing men in a remote part of the Amazon rainforest, near the border with Peru

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