This is the horrific moment a man playing on the beach with his friends was brutally knocked down by an out-of-control Jet Ski.

Footage captured the moment the vehicle mounted the beach before smashing into the unsuspecting victim, sending him somersaulting through the air.

Moments later he crashes back into the sand hard, while his shocked friends run over to help.

It is not known exactly when or where the footage was taken, or how badly injured the man was.

The clip has since been posted on YouTube where it has gone viral, attracting hundreds of thousands of views.

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