Police searched Thursday for a motive in the slaying of a vocational school instructor who was allegedly shot by a student during a class for security guards.
Law Thien Huynh, 22, argued with the instructor before leaving the classroom and returning with a firearm, police Lt. Paul Vernon said.
The teacher was shot at near point-blank range Wednesday afternoon, Vernon said. No one else was hurt.
Huynh was arrested for investigation of murder. Calls to a telephone listing for Huynh were not answered Thursday
Classmate Jermaine Walter told KABC that Huynh often asked questions in the security class about shooting and killing people.
After Roberto Herrera was shot, the gunman put his weapon down, told classmates to call 911 and walked outside to smoke a cigarette before being arrested, students told KABC.
The 44-year-old Herrera "was the nicest guy. He'd give his last dollar to you," Walter told the TV station near a memorial of a flower arrangement and a dozen candles outside Coast Career Institute, which remained closed Thursday.
Herrera had taught a 24-week course in security guard training at the school for the past three years, Vernon said. Teaching was a side job to his regular job as a security guard.