New video shows the horrific shooting at the Kansas City Super Bowl parade ... and this footage graphically shows injured people falling to the ground and the crowd scattering.

The video is from a nearby apartment surveillance camera. You see the crowd milling around after the parade ended, and then suddenly a flurry of shots ring out.

As several people fall to the ground, presumably injured, you see where the gun was fired based on where the crowd disburses.

You also see cops rushing toward the area where the gunman appears to have fired.

As we reported, a man who was shot says his wife and daughter heard a woman tell a man in the crowd, "Don't do it. Not here. This is stupid," shortly before shots rang out.

Several parade-goers tackled a man carrying a gun shortly after the shooting. Police swooped in and took him into custody. At least 3 people have been detained in connection to the shooting.