Authorities were in the 12900 block of Foothill Boulevard on reports of a man entering a business and physically harming employees.
When officers arrived, they found the man with a large pointy stick, authorities said. Officers chased the suspect and when he tried to hit them with a brick, the shooting occurred.
The suspect was shot once in the torso and taken to a hospital in an unknown condition, authorities said.
No further information was immediately released.
Anyone with more information was urged to call the L.A. County sheriff's homicide bureau at (323) 890-5500. Those wishing to remain anonymous may call Crime Stoppers at (800) 222-8477.