According to the San Diego Police Department, just before 6 a.m. Wednesday, two men were arguing in an apartment-complex parking lot at 6800 Potomac St. when the suspect shot the other man.
The suspect fled, while the 52-year-old victim went to Paradise Valley Hospital. He was then transported via ambulance to Scripps Mercy Hospital and treated for a gunshot wound to his left upper chest, police said.
No specific description of the suspect was provided.
Police are asking anyone with information about the shooting to call 619-531-2000 or Crime Stoppers at 888-580-8477.