The shooting occurred on the 500 block of North Caswell Avenue just after 9 p.m. Thursday, according to Pomona Police.
Firefighters nearby witnessed the shooting and gave police an accurate description of the shooter. No suspect or weapon was located during a subsequent search.
The victim was reportedly conscious and breathing after being shot. The victim was airlifted to USC Medical Center in unknown condition.
There were several people in the area attending a candlelight vigil for a victim who was fatally shot early Wednesday morning, according to police.