FOOTAGE of a Buckingham Palace guard knocking out a tourist has surfaced online.

The video shows a man provoking the guard by doing the robot dance just inches from his body.

The minder remains expressionless, before suddenly swinging a fist into the man’s face – sending him crashing to the floor.

He’s then seen lying motionless on the ground as tourists gather around and the guard picks up his bearskin, blown off his head by the force of the punch he threw.

However, the shocking encounter was actually an elaborate prank for YouTube channel Trollstation.

Still, it’ll certainly put people off antagonising the Queen’s security staff in future.

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