Ugandan wildlife authorities have reintroduced rhinos into a remote protected area where they were once poached into extinction, an event seen by conservationists as a milestone in efforts to support the recovery of a species threatened by poaching.

On Tuesday, two southern white rhinos from a private ranch in the East African country were reintroduced into Kidepo Valley National Park in the country's northeast. Two more rhinos in metallic crates arrived there on Thursday.