Transcript for Police investigating motive in deadly rush hour traffic stop gun battle
And back home, new reporting after a traffic stop that turned deadly in California. The driver pulling out a rifle then firing in rush hour. One officer did not survive. Matt Gutman is on the scene tonight. Reporter: Tonight, police still investigating that deadly gun battle in the thick of rush hour traffic. Dozens of rounds fired. You can hear those pops and see the puffs of smoke. When it ended, three officers were shot. One of them, Andrew Moye, killed. They're requesting for medical aid on the helipad. Reporter: It began minutes earlier when motorcycle officer Moye pulled over this white pickup in what police say was a traffic stop. Police say as Moye was doing paperwork to impound the vehicle, the suspect, Aaron Luther, went to his truck, pulled out a long gun, and began firing. In this video filmed by a terrified motorist, you can see him firing, dressed in black. And despite being mortally wounded, officer Moye managed to radio for backup. Those reinforcements arriving. That's when an additional two officers were hit, one critically. One officer dragged to safety. Then officers guns at the read sprint towards Moye, loading him onto to a patrol helicopter. Stray bullets slamming into nearby cars. It hit straight into the middle of my windshield, missing my head and my two children in the backseat. Reporter: Overnight, that solemn procession of chp officers mourning accompanying Moye's body. This was his dream job. He loved going to work. Reporter: Overnight Luther's father the suspect had been arguing with his wife. I love him, and I'm sorry for the policeman. I know police are investigating why the suspect jumped out, and how he got that weapon. Reporter: That's right, because he's a felon, and they're not allowed to have weapons of any kind. Luther had a rap sheet going back 25 years, and officers want to know why he had a gun of any kind, much less that customized assault-style rifle. Matt, thank you.
This transcript has been automatically generated and may not be 100% accurate.