Brazil's federal police have said that reports that the bodies of British journalist Dom Phillips and indigenous expert Bruno Pereira had been found in the Amazon were not correct.
Police said in a statement that only biological material and belongings of the missing men had been found so far, as previously announced.
News outlet G1 had reported earlier in the day, quoting Mr Phillips' wife, that the two men had been found dead.
A police statement said clothing belonging to Mr Pereira had been found, including a health identification card in his name, and a backpack with clothes belonging to Mr Phillips, along with the boots of both men.
A fireman leading a search team told reporters that the Equinox backpack, containing clothes and a laptop, was found tied to a half-sunken tree trunk in the area that the two men were last seen on 5 June.
Earlier, Elizeu Mayaruna, who works for the indigenous agency Funai, said while searching the forest along the Itacoai river on Saturday, he found clothes, a tarp and a bottle of motor oil.
Mr Mayaruna and two other members of an indigenous search team acquainted with Mr Pereira, a former Funai official, said they recognised a shirt and pants that belonged to him.
Witnesses said they saw Mr Pereira and Mr Phillips, a freelance reporter who has written for the Guardian and Washington Post, travelling down that river.
The two men were on a reporting trip in the remote jungle area near the border with Peru and Colombia that is home to the world's largest number of uncontacted indigenous people. The wild region has lured cocaine-smuggling gangs, along with illegal loggers, miners and hunters.
News of the pair's disappearance has resonated globally, with Brazilian icons from soccer great Pele to singer Caetano Veloso joining politicians, environmentalists and human rights activists in urging President Jair Bolsonaro to step up the search.
Witnesses saw the stretch of riverbank where Mr Mayaruna discovered the clothing cordoned off by police yesterday morning as investigators scoured the area, with a half dozen boats ferrying police, soldiers and firefighters back and forth.
There was no immediate comment from the Brazilian government on the search findings.
Mr Bolsonaro, who last year faced tough questioning from Mr Phillips at news conferences about weakening environmental law enforcement in Brazil, said last week that the two men "were on an adventure that is not recommended" and suggested that they could have been executed.
State police detectives involved in the investigation have said they are focusing on poachers and illegal fisherman in the area, who clashed often with Mr Pereira as he organised indigenous patrols of the local reservation.
Police have arrested one fisherman, Amarildo da Costa, known as "Pelado," on a weapons charge and are keeping him in custody as they investigate whether he is involved in the men's disappearance.
Mr Costa's lawyers and family have said he fished legally on the river and denied he had any role in the men's disappearance.
Some 150 soldiers had been deployed via riverboats to hunt for the missing men and interview locals, joining indigenous search teams who have been looking for the pair for a week.
