A handcuffed girl was seen being taken into custody by police and referred as a "person of interest" by Zepperman.
Police officials said the shooting suspect is about 12 years old and the weapon of the shooter has been recovered by police.
Police officials told reporters that they don't know the exact number of students on the scene when the shooting happened and it is still too early in the investigation to determine the motive of the suspect.
There was a heavy police presence at the location and the campus was on lockdown. A lot of anxious parents and relatives were waiting outside the campus.
All of the parents of the victims have been notified, said authorities.
Salvador Castro Middle School has a total enrollment of 428 students and 22 full-time teachers. More than 92 percent of the students are Hispanic, according the data on the website of the www.localschooldirectory.com.
Feb.2,2018--Parents wait to pick up their children outside Salvador Castro Middle School in Los Angeles, the United States, Feb. 1, 2018. Five people were injured, including two students shot, in a classroom shooting Thursday at the Salvador Castro Middle School in the western U.S. city of Los Angeles, local authorities said. (Xinhua/Zhao Hanrong)