SAN Francisco Police are on the hunt for four armed gunmen, dressed in dark jeans and hoodies, who opened fire outside a high school about 3pm (local time).
The New York Post reports students had just been let out of class at the June Jordan School for Equity when the group of armed men started shooting at a 15-year-old girl and three young men.
Local teenager Fernando Rodriguez told the San Francisco Chronicle he heard six "pops" before people started to flee the area.
Police later told the media the girl injured in the shooting may have been the target of the attack - she is presently fighting life threatening injuries in hospital.
As yet no one has been taken into custody in relation to the incident.