Here we are on that "Chute 2 Wund!" kick again.

They waited until he was a few feet away and warned him of the consequences earlier. A leg shot is a harder shot to make and if they miss, they risk a ricochet along the ground, which is extremely dangerous. A center of mass shot would more likely hit and if it missed, travel in a predictable line to a wall. As for the number of times, probably multiple officers shot him.