The female suspect led officers on a high-speed chase through Buena Park, Tustin and Santa Ana, where it ended when police opened fire and killed the driver while she was still behind the wheel on 17th and Grand.
"I saw a black Honda coming, and then the cops were coming after it, and then I just heard three gun shots," said witness Juan Guerrero.
Police have not yet said why they opened fire.
The Honda crashed outside a Food 4 Less on Grand Avenue.
After killing the driver, police moved in to the car, discovering an 18-month-old girl in the back seat. She was uninjured and was taken to Orangewood Children's Home.
It is unclear what the suspect's relation is to baby.
The area of 17th and Grand will be closed while police clear the scene and investigate.
MORE LOCAL HEADLINES FROM ORANGE COUNTY
SEND TIP || REPORT TYPO || TWEET @abc7 || WIDGET