The FBI is not aware of any motive or ideology that drove a 16-year-old boy to shoot and kill two teenage schoolmates and injure several others on his birthday.
A 14-year-old boy and a 16-year-old girl arrived in critical condition at a nearby hospital but later died.
The suspect is in "grave condition" after surviving a gunshot wound to the head, according to the Los Angeles County Sheriff’s Department.
Police say today is his birthday.
Three other people are being treated for injuries at area hospitals.
As dramatic aerial footage showed students being escorted from campus by armed deputies, politicians and gun control advocates railed against conditions they argue paved the way for yet another deadly school shooting.
News of the shooting was breaking as Senator Chris Murphy was introducing a measure calling for universal background checks, a proposal that was shut down by GOP senators.
"Republicans objected, my motion failed, and now, as a consequence, the slaughter of our children will continue," he said. "Devastating."
California Senator Kamala Harris told MSNBC that it's "pathetic that people yield to a gun lobby on an issue that affects all our children."
Katie Hill, the former California Congresswoman who recently stepped down from office, said in the statement that the "time is now" to defeat gun control opponents.
Follow updates as they happened.
Authorities in Santa Clarita, California are responding to reports of a shooting at Saugus High School, roughly 40 miles north of Los Angeles.
The Los Angeles County Fire Department has reported that least six people have been injured. It was not immediately clear whether students were reported as injured or if they had been shot.
Authorities are canvassing the region and looking for the suspect, according to local reports. At least two victims were rushed to the hospital, though it remains unclear what condition they are in. Reports say there were at least six or seven victims in the incident.
Police believe they may have spotted the suspect in the bushes behind the school. Authorities are circling the area with deputy vehicles and staging police in the region in case they have a suspect sighting.
So far there are no confirmed sightings of a suspect, though police have reportedly deployed units to a specific residence in the area.
Officials have urged local residents to stay indoors and lock their homes as the suspect is still missing. Police have only said the assailant was seen wearing dark clothing and may have been spotted near the school.
Residents say nearby schools are on lockdown as police survey the area. A student who goes to the high school tells KTLA they regularly participate in school shooting drills.
A hospital official confirms there are two patients in critical condition at the hospital and three others are in route.
One victim was rushed in a sheriff's vehicle to the hospital and several others were loaded in ambulance units, the Henry Mayo hospital tells local media. There are still no reports confirming the identities of any of the victims.
A parent tells KTLA her daughter was in a classroom when another student who was shot ran into their room during the apparent school shooting. Others tried to stop the bleeding, the mother says.
Police tell The Independent the suspect is a 15-year-old Asian male wearing a black shirt, hat and blue jeans. The school is on lockdown, along with three other nearby elementary schools.
There are two patients currently in critical condition at the Henry Mayo hospital, and three others on the way.
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