The incident occurred in the 1100 block of West Hemlock Way around 1:15 a.m.
Responding crews found an 18-year-old man suffering from gunshot wounds in the middle of the street. The victim was walking on the street when a suspect drove up, according to Santa Ana police Cmdr. Enrique Esparza.
"The suspect got out of the car and started shooting," he said, adding that the victim was struck in the legs, hip, hand and a toe.
Four rounds struck a nearby apartment, shattering a window and nearly hitting a grandmother sleeping inside. She was visiting from Mexico and sleeping on the living room couch, according to 15-year-old Bryette Baltazar.
"She just got up when it went through the window," Baltazar said. "It's been a while since that happened. I want to move."
The 18-year-old victim was taken to a local trauma center in unknown condition.
Investigators believe the shooting was possibly gang-related. No arrests have been made in the case.
CNS contributed to this report.