there was two officers there then and they were in trouble. >> off camera, jerry cain pushes officer incline and then on the dash cam, cain's son, joe, appears with a gun. >> bill is stumbling down this incline. he shoots at him. he didn't have time to get his weapon out. he hit him many times in the body, in the back. >> at that point, the second officer tries to help evans with the 16-year-old turning his weapon on him. >> officer down, officer down. 277 westbound. >> a delivery driver witnesses the whole scene. >> these guys just shot a police officer. >> through the statements of the driver, this kid was very methodical, very slow, knew exactly what he was doing and he handled that ak-47 like a military person would. >> the father/son team calmly gets back in the van and takes off leaving the officers bleeding on the ground. shortly after, more police arrive and find that officer evans is alive but just barely. >> and there was about three officers standing over him and they were saying, bill, you're going to be okay, you're going to be okay. there was quite a bit of blood around