This was the moment a man jumped off a bridge into a river in Montana's Rocky Mountains and knocked himself unconscious, before being rescued by an onlooker.

Footage from July 26 shows the man's leap off Belton Bridge into Flathead River in Glacier National Park.

The incident causes multiple gasps from onlookers. The man is seen floating face down from behind a large rock. But a man, realising the danger, jumps in to pull him to safety,

The filmer, Seth Woodiwiss, wrote: "While filming people from my group about to jump off, a person jumped off of the bridge and into the water.

"Everyone thought it was OK like the previous jumpers.

"Though this one was different, he was floating face down when he resurfaced to the top of the water.

"Upon seeing this, people started yelling to get him.

"A guy jumped off of the bridge and subsequently brought him to shore.

"He was helped by an EMT and nurse that were there with their own groups.

"An ambulance was called and before they got there, the man regained consciousness and was inspected by the ambulance when they arrived."