Authorities are working to obtain any other video from campus and cell phone video from students.
Police set up a location at a nearby park for parents to retrieve their children.
They confirmed a message - "Saugus, have fun at school tomorrow" - was posted to the Instagram account believed to belong to the suspect before the shooting and were trying to determine its relevance and whether someone else with access to the account might have written it.
It was not immediately clear if the victims suffered gunshot wounds or other injuries. "And I think one of the hardest parts about it is, you know, what are we supposed to say at this point?"
"I was anxious about my friends who might be affected by this". They said they were hiding and they were scared. They were paired on engineering projects during the last school year and he came to her house to work on them.More news: Airtel slips into Rs 23,045 crore Q2 net loss on AGR hit
Saugus High's security is provided by one unarmed sheriff's deputy and nine "campus supervisors" who act as guards, said to Collyn Nielson, chief administrative officer for the William S. Hart Union High School District.
"Everyone thought it was a balloon, and it got really quiet".
But then several students rushed in, screaming.
"You can't outrun a gun", she said.
"I automatically knew something bad was happening", he says.
"My son was in the quad where it happened and as soon as he saw the shooting he ran, and we have a meeting space and he ran and I met him there", Skiba said.More news: Ousted ambassador testifies in President Trump impeachment probe
Vice President Mike Pence gave his condolences to families of the victims.
The L.A. County Sheriff's Department responded to the shooting, and discovered the alleged shooter was among those students injured in the incident, which occurred at 7:30 a.m., 20 minutes before classes were to begin. "We've passed four different pieces of legislation that would make an immediate impact on gun violence".
Police have executed a search warrant and are now investigating the suspect's home on the 22900 block of Sycamore Creek Drive for clues in the shooting.
The scene at Saugus High School was reminiscent of other mass shootings at USA schools, including Marjory Stoneman Douglas High School in Parkland, Florida, where a former student with an assault gun killed 17 people on February 14, 2018.
The scene at Saugus High School was reminiscent of other mass shootings at US schools, including Marjory Stoneman Douglas High School in Parkland, Fla., where a former student with an assault gun killed 17 people on February 14, 2018.More news: Mahesh Babu's daughter Sitara becomes a star; gives voice in 'Frozen 2'