Police have arrested a second suspect in the disappearance of British journalist Dom Phillips and indigenous expert Bruno Pereira.
Police said the suspect, Oseney da Costa de Oliveira, 41, was the brother of the first suspect arrested.
Amarildo da Costa de Oliveira, 41, also known as Pelado, has been named as a suspect in the disappearance but arrested for allegedly carrying a firearm without a permit, a common practice in the region.
He is thought to have been among a group of men who threatened the missing men near an indigenous territory on June 4.
It comes after police said personal items belonging to the two missing men were discovered in a river on Sunday.
Mr Phillips, 57, and Brazilian indigenous expert Bruno Pereira, 41, vanished from a remote part of the Amazon last week and are believed to have last been seen early on June 5 in the Sao Rafael community.
Earlier, the Brazilian ambassador to the UK apologised to Mr Phillips’ family after they were incorrectly told his body had been found.
According to The Guardian, the family received a call from an aide to the ambassador early on Monday saying their bodies had been discovered tied to trees in the rainforest.
However, Mr Phillips’ brother-in-law, Paul Sherwood, confirmed to the PA news agency on Tuesday that ambassador Fred Arruda had written to the family to say the statement was incorrect.
He went on to say the embassy had been “misled” by information it had received from “investigating officials”.
Mr Arruda insisted: “The search operation will go on, with no efforts being spared.”
He added: “Our thoughts remain with Dom, Bruno, yourselves and the other members of both families.”
On Saturday, separate reports emerged that police had discovered human matter in the Itaquai River, near Atalaia do Norte’s port.
Authorities previously said blood found on Pelado’s boat had been sent for analysis.
A GoFundMe set up by friends of the men neared 37,000 dollars (£30,732) early on Wednesday morning.