Bystanders assist arrest with effective control

A police officer struggles to arrest a man by wrist control alone. Two bystanders intervene and clinch with the man around the upper body. One of the former bystanders transitions to control the legs, and together execute a very effective takedown and control of the man. Throughout the takedown, the police officer continues to attempt some kind of wrist/arm control.

Slam while applying submission from ground

MMA fighter attempts triangle choke from bottom ground position. His opponent raises and slams him into the floor, resulting in a knockout. This is exceptionally dangerous and would most likely result in death on a hard surface.

This can be avoided by using techniques which break the posture of the person attempting the slam and bring them back to the ground, or by abandoning the technique as below. The slam is attempted by the same MMA fighter as the above video: