Former UFC fighter, 45-year-old Brazilian Geronimo dos Santos, went missing while swimming in the Amazon basin.
Idman.Biz reports with reference to the "Lance" portal that the incident occurred in the Rio Negro River, which is the largest left tributary of the Amazon River.
It is reported that Geronimo entered the water at 10:00 local time and has not surfaced since.
Search and rescue operations began several hours after the incident.
According to local authorities, the incident occurred in an extremely dangerous part of the river. In this area, a sandy area hides a sudden deep cliff and a strong current. According to the preliminary version of the investigation, dos Santos fell into this depth, and the strong current carried him to the upper reaches of the river.