A man accidentally fell under a bus, amputating both his legs. A bystander captured the aftermath on video. The situation on the video is an example of how it should not look like. Everyone around is hysterical and just running around.
If you happen to witness a similar event, keep calm. If the victim is conscious, speak to them in a calm voice and stop the arterial bleeding. Then call the emergency service line and, without hysterical scenes, tell your location and describe to the operator what is happening. If there are more of you in the place, task the others to get all the points as soon as possible.
