The young man burst into the Learning Center on the campus in San Bruno screaming he had been shot. He had been hit by a bullet in his buttocks.
The victim was taken to San Francisco General Hospital.
A relative told ABC7 the victim is a 20-year-old Skyline student and that an argument led to the shooting.
Police confirm the shooting happened around 1:30 p.m. after an argument broke out between two groups in one of the campus parking lots. They believe the shooting was an isolated incident and the victim was targeted by the suspects.
The suspects are described as three African American men, who fled the school in a fluorescent purple Ford Escort.
Student Raydan Alhubaishy was walking to his car when he heard shots and saw the suspects.
"I didn't see the victim, I saw the people who were holding the gun, they were running," he said.
The school sent out text messages to most of the students, alerting them of the shooting and cautioning them to shelter in place until they could be evacuated.
While the hunt for suspects ranged across campus, many students were locked inside classrooms. Carlos Cervantes was released from the library while the manhunt continued.
"We were walking behind the cops and they were waiting for someone, I got scared because I thought maybe the guy would come out and there might be some shooting," Cervantes said.
The editor of the school's paper, Andrew Lidwell, spoke to a teacher who saw the victim before he was taken away.
"There was blood on his shirt. He was bleeding from the lower torso. He was screaming about being shot. According to the teacher, he ran in, dropped his backpack and ran back out," Lidwell said.
"There were no students inside the classes or the school who were targeted. This was a specific, looks like an altercation in the parking lot between two groups of males," San Bruno Police Cmdr. Marc Catalano said.
The victim is expected to be OK. His injuries are said to be non-life threatening.
Classes are canceled for Thursday, but will resume on Friday.