SANTA CLARITA (CBSLA) – A girl and a boy were killed and three of their classmates wounded when a fellow student opened fire on his birthday at Saugus High School in Santa Clarita Thursday morning, authorities said. The suspect was hospitalized with a self-inflicted gunshot wound.

The shooting occurred just after 7:30 a.m. at the school located at 21900 Centurion Way. Responding Los Angeles County Sheriff’s deputies arrived to find six students lying wounded in the campus quad, one of whom they learned later was the suspect. He was identified to CBS News as Nathaniel Berhow.

“The suspect was later identified as one of the victims who was found in the quad,” L.A. County Sheriff’s Capt. Kent Wegener said at a late Thursday morning news conference.

Two of the victims, a 16-year-old girl and a 14-year-old boy, died from their injuries after being rushed to Henry Mayo Newhall Hospital.

Classmate Micah Turner told CBS2 she made eye contact with the shooter as he opened fire.

“He was wearing black sunglasses at the time, and he looked very familiar,” Turner said. “And then he shot two people, and I saw that happen, and I saw him fire: one, two three. And then I knew I needed to get out of here. And we looked at each other.”

“I just saw like one head just like fall, I didn’t really pay attention to who it was,” she added. “I just saw a body fall and my first instict was to get out of there and to find my sister.”

Two more girls, ages 14 and 15, along with a 14-year-old boy, were hospitalized. The girls were both said to be in good and fair condition at Providence Holy Cross Medical Center in Mission Hills. A hospital spokesperson late Thursday afternoon said they were “in good spirits.”

Henry Mayo Hospital officials said one person who was brought to the hospital in good condition — believed to be the 14-year-old boy — was treated and released early Thursday afternoon.

Berhow turned 16 on Thursday, Wegener said. He was hospitalized in grave condition, L.A. Sheriff Alex Villanueva said. His gun, a .45-caliber semi-automatic pistol, was found at the scene with no rounds in it.

“He is identified as a 16-year-old male, whose birthday is today,” Wegener said.

The shooting was captured on surveillance video.

“Detectives have reviewed the video at the scene which clearly show the subject in the quad withdraw a handgun from his backpack, shoot and wound five people, and then shoot himself in the head,” Wegener said.

Villanueva confirmed Thursday that one of the victims who died was the family member of a sheriff’s department employee.

The suspect lives in the 22900 block of Sycamore Creek Drive. Deputies, along with the FBI and ATF, raided the location. The suspect’s mother and girlfriend were being interviewed by detectives. It’s unclear who owned the gun used in the shooting.

Investigators are also looking into whether the shooter posted any warnings on social media.

“I can tell you that we have checked for recent threats involving Saugus High School,” Wegener said. “We identified two which were both investigated and had no nexus to this subject.”

One student told CBS2 he recently reported a social media threat to police prior to the shooting.

“We found an Instagram account, like in their bio,” student Ryan Payae told CBS2. “It said ‘Saugus have fun at school tomorrow,’ so I got like speechless and I didn’t know what to do, so I reported it to police.”

In an afternoon press conference, Wegener said that the Instagram account believed to be Berhow’s wrote: “Saugus, have fun at school tomorrow.” An Instagram spokesperson later told CBSLA that they had “disabled this account for violating our policies,” and said, “We can confirm it did not belong to the shooter.”

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As news of the shooting first broke, the sheriff’s department initially reported that the suspect had escaped. Surrounding roads were shut down and a multi-block search perimeter was established. Residents were ordered to lock their doors and stay inside.

An off-duty sheriff’s deputy and two off-duty police officers with family members at Saugus High were the first to respond, Villanueva said.

However, just after 9:30 a.m., Villanueva confirmed that the suspect was in custody and was being treated at a hospital.

“The lone suspect is in custody and the weapon has been seized,” the William S. Hart Union High School District wrote in an email to parents.

Classes had just gotten underway when the shooting happened, so the campus was not completely full.

“All of a sudden, we hear this distinctive sound outside, so my teacher quickly sprang to his feet,” student Mason Peters told CBS2. “(He) got up, locked the door, asked one of the students to get the keys. So we reinforced it. Turned off all the lights. Then we got a bunch of desks and stuff and reinforced the doors. And then we all stayed hidden.”

Saugus High, which has about 2,300 students, and all other schools in the William S. Hart Union High School District were placed on lockdown for several hours. All lockdowns were later lifted.

“I was in class just doing my work as usual and all of a sudden I heard loud pops, loud bangs…two seconds later there were people sprinting, screaming…two students came into our room saying someone has a gun, so we locked the room,” student Shauna said.

Parent Brian Skiba described his daughter’s experience.

“She heard the shots as well, she was in the quad where it started, and ran to the band room and locked the door behind her and told everybody to get down,” Skiba told CBS2 by phone.

“My daughter’s still in the band room, they’ve got a policeman with them,” Skiba added. “They’re still in lockdown. They’re only clearing it classroom by classroom.”

Lisa told CBS2 that her son was on his way to school when he got news of the shooting.

“He was walking to school about 7:30…He called me and said that his friends called him and told him not to come to school because he heard gunshots,” she said.

Saugus students were being interviewed by detectives as they were slowly being released from the school. As of noon, students were still at the school As they were slowly being released from the school, Saugus High students were being bussed to Central Park, where they could reunite with their parents or guardians.

All schools in the Hart School District were to be closed Friday, a district spokesperson said.

There was still no word on a motive in the shooting.

Vice President Mike Pence, who was speaking Thursday at the NASA Ames Research Center in Mountain View in Northern California, took a moment to offer condolences to the victims.

Pence said President Donald Trump asked that he convey “his deepest sympathies to the families of the victims and the entire Santa Clarita community.”

The vice president also vowed “to bring the scourge of mass shootings to an end, and we will not rest or relent until we end this evil in our time and make our schools and our communities safe again.”

The President later tweeted, “We continue to monitor the terrible events at Saugus High School in Santa Clarita, California through our ongoing communications with Local, State, and Federal Authorities. We send our deepest condolences to the families and friends of those tragically lost, and we pray for the speedy recovery of the wounded.”