Brazilian police found drugs and weapons on one man linked to the disappearance of a British journalist and an Indigenous advocate.

The disappearance of journalist and longtime Guardian contributor Dom Phillips and advocate for Indigenous people Bruno Araújo Pereira is still under investigation by Amazon authorities after the duo went missing on Sunday in a remote corner of the rainforest, BBC News reports.

Last Wednesday, the police in the far west of Brazil arrested a man in possession of drugs, a shotgun and ammunition restricted for military use. Earlier that day, a man named Amarildo da Costa de Oliveira on similar charges was detained, but authorities say 'no evidence of crime' was found in search for the missing journalist, and it was 'too early' to link any suspect directly to the missing pair, according to the Guardian.

"We have material that makes us suspect there is a link to the fact," said Carlos Alberto Mansur. "But it's still just a suspicion. It's still being investigated. "For now, our main job is searching, and our hope is still to find them alive."

No Indication of Crime Yet

No trace has been found of the two, or the boat they were travelling in since they were reported missing. The authorities are hopeful that they are still alive and that they only lost their way in the "very complex area".

"We still don't have a strong indication a crime was committed," Carlos said.

However, according to witnesses, Da Costa, also known as 'Pelado', and two other armed men stopped and threatened Phillips and Pereira on Saturday morning at the side of the Itaquaí river in Amazonas state. The police later on seized Da Costa's boat.

Pereira, 41, is a longtime advocate and 'dedicated defender' of the Indigenous rights, while Phillips, 57, visited the region researching a book on sustainable development. According to the Guardian, both got death threats from drug traffickers and illegal miners, loggers and hunters who covet land in a region rich with natural resources.

The two were supposed to return from the two-day reporting trip but did not arrive as scheduled at the town of Atalaia do Norte.

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Brazil Steps Up Search for the Missing Duo

Brazil's personalities from the sporting and arts worlds joined in the petition to speed up search led by Alessandra Sampaio, Phillips wife. Meanwhile, lead investigator and his team say they were "pursuing all lines of inquiry".

Three-time World Cup winner Pelé, Everton, and Brazil forward Richarlison and Walter Casagrande, a former Brazilian player, showed support. Moreover, singer Gaby Amarantos, actor Camila Pitanga and Sonia Guajajara, an Indigenous leader all made appeals on social media as well.

Britain's shadow foreign secretary, David Lammy, urged Brazilian authorities "to do all they can to find them as soon as possible and for the Foreign Office to use all the diplomatic channels at its disposal." There have been disappointment and even anger over the "lack of urgency shown by Brazilian authorities."

Nonetheless, authorities claim the search operation had expanded by Wednesday and jungle warfare specialists were being deployed to find traces of the men in the Javari's dense forests.

Related article: British Journalist Goes Missing in a Remote Part of the Amazon