Indigenous groups scour forests and rivers for Dom Phillips and Bruno Pereira

Pereira, a celebrated Brazilian Indigenous expert, disappeared early last Sunday while returning from a reporting trip deep into the Amazon with the British journalist and longtime Guardian collaborator Dom Phillips.

As he scanned the brown waters, Matis said he was on the lookout for even the tiniest suggestion that Pereira and Phillips might have been there: a backpack or T-shirt, a can of oil, a lifejacket or perhaps the seat of a boat.

Yet there was nothing but the occasional submerged tree trunk to be seen in the river that meanders towards the Javari Indigenous Reserve, whose inhabitants Phillips was in the region to interview.

Possuelo, a close friend of Pereira, recalled how exactly a week earlier he had helped the two missing men load their bags on to a boat as they began their three-day trip along the River Itaquaí.