This is the dramatic moment a man came face to face with a mountain lion while on a trek through a mountain range.
The incident was captured on camera and took place at the Glacier National Park in Montana, on the Canada-United States border.
In the clip the man talks gently while zooming in on the mountain lion, also known as a cougar, with what is presumably his camera phone.
He speculates that the predator is probably around 50 feet away from him and points out that it is staring straight at him.
The cougar initially seems quite relaxed and content and doesn’t appear to be causing the man any major problems, other than the fact that it blocked his path.
But suddenly it gets to its feet and with its head down – as if in a stalking position – begins walking towards him.
The video maker reacts in panic and starts shouting at the mountain lion in the hope of snapping it out of its predatory state and scaring it away.
But at first the cougar doesn’t appear to be too bothered by the noise coming from the man, and although it momentarily stops in its tracks, it continues to look over towards him.
The cougar then looks off to its right and begins descending the grass verge – it is unclear at this point whether the predator is heading off or whether it is looking for another way around to the man.
It then crouches down on all-fours and appears to be focusing on the man before getting ready to strike.
Realising that he could well be in danger, the video maker shouts at the animal again in a desperate bid to scare it away.
But the mountain lion continues to wander slowly towards him and can be heard breaking branches as it crawls through the thicket.
The cougar then begins walking away from the man but carries on looking over towards him every so often to check him out.
Later in the video the mountain lion takes one last look at the filmmaker before heading off into the trees and becoming hidden from view.
The clip concludes with the man turning the camera around to film himself and acknowledging that he was worried the animal was going to attack him before commenting that the experience was awesome.
Mountain lion attacks are very rare as the predators do not generally recognise humans as prey.
Attacks may occur when juveniles leave their mothers and look for their own territory or if the animal is suffering from severe starvation, however.