Sheriff's deputies said they were called to the Los Cerritos Center on Gridley Road around 4 p.m. Video from the Citizen App shows crime scene tape near the Chick-fil-A in the area.
Deputies say a juvenile male with a gunshot wound was treated at the scene and transported to an area hospital, where he was pronounced dead.
Investigators say an altercation took place outside of a business in the area, and during the fight, the suspect shot the victim before taking off on foot.
Further details, including a description of the shooter, were not immediately available. The investigation into the deadly shooting is ongoing.
Anyone with information about this incident is encouraged to contact the Los Angeles County Sheriff's Department's Homicide Bureau at (323) 890-5500.