My understanding is that this happened in Brazil. According to the information I got, the victim begs for the captors to kill him, apparently because he’d been tortured.
The video shows him being held on a leash in form of a rope around his neck. It’s possible that he was being dragged and/or choked with the rope. Either way, the captors granted him the wish and killed him execution style by shooting him in the head at close range.