>> go back. >> as far as i can. it's such a blur. oh, wait. i think i seen a muzzle flash. >> where? >> muzzle flash. >> listen. >> go ahead. we'll see. >> boom, boom, boom. right into the car. >> muzzle flash. muzzle flash. >> muzzle flash. >> muzzle flash. >> right here. this is it. boom, boom, boom, boom. >> they can't see his face from the camera but in a wired philly the trail isn't cold just yet. >> here we go. >> armed with this information detectives can tap into their private cameras in the days to come to try and catch their killer. >> if you can, take a snapshot. >> i took a snapshot. >> without you i am nothing. >> it's my final night embedding with the tactical force. and once again i'm with officers pinto and artiz. as we hit the streets, a job comes up on their computer. >> mentally ill personal apparently who's holding a female inside.