Excessive force by Police? Watch the video...

Are these police officers stepped over the line in punching and kicking or was this necessary to apprehend this suspect?

There are of course two sides of this story:

"The question is, is the force appropriate for the situation?" Police Chief James White asked. "Is it appropriate for the resistance? I don't know any of that."
Activists with the St. Louis County NAACP don't think it was appropriate .
Watch the video