The cop catches someone doing something illegal, and the suspect runs. As he's chasing him down, he calls on his walkie-talkie radio thing and requests backup. I would be including other information (below), but what i'm missing is the beginning part- how does he initiate the call, how does he request backup, and how does he end the request?
So, now for a game of "fill in the blanks!"
_______________ suspect is on foot, headed south 8th street ______________.