After Hamilton celebrated his title success in the stadium, he sprinted off around the circuit to get back to the garage and celebrate with the rest of this team. Fans had also started to invade the circuit and of course, they chased after him.
One person looked particularly keen to get an autograph or something and ended up slamming into an innocent bystander who was giving Lewis a high-five, and of course the whole thing was captured on TV.
(Skip to the 19 second mark for the collision)
What makes it especially brutal is the way the guy just gets up and carries on like nothing happened! He definitely needs a penalty for causing an avoidable collision. Maybe a five-row penalty in the grandstand for the next race he attends?