British journalist Dom Phillips and indigenous expert Bruno Pereira were shot dead with hunting ammunition, Brazilian police have said.
A day after police identified Mr Phillips' remains, the second set of remains were confirmed as those of Mr Pereira on Saturday.
A third suspect in the murders has been taken into custody, police added.
The two went missing while on a reporting trip in the Javari Valley, in Brazil's Amazonas state on 5 June.
Ten days later, human remains were found after a suspect confessed to burying their bodies and led police to the spot where the remains were found, police said.
The suspect, a fisherman named by police as Amarildo da Costa de Oliveira, was the first person arrested.
His brother, Oseney da Costa, was also arrested earlier this week - he denies any involvement in the murders.
A third suspect was arrested on Saturday. Jeferson da Silva Lima, also known as Pelado da Dinha, turned himself into a police station in the city of Atalaia do Norte, according to police.
Mr Phillips, 57, had been living in Brazil for more than a decade and was a long-time contributor to the Guardian newspaper - he was in the area researching a book.
Mr Pereira, 41, who was on leave from his post with the government's indigenous affairs agency Funai, was an expert on isolated tribes in the Amazon.
Mr Pereira had received death threats prior to taking the trip, indigenous rights groups said.
The area in which they were travelling has become known for illegal fishing, mining, logging and drug-trafficking activities.
The region is known for violent conflicts between these various criminal groups, government agents and indigenous people. It was these conflicts that Mr Phillips and Mr Pereira were documenting.