Suspect knocks out police officer as he struggles during arrest

Here is the video, filmed by a witness, of an arrest that is, to say the least, messy. While two officers try to put a suspect in their car, this one resists, and makes fall one of the policemen on the ground. Stunned, the policeman stays on the ground, and his colleague prefers to help him than to pursue the bandit, who takes advantage of the situation to flee.