BY ALEX SUNDBY, SARAH LYNCH BALDWIN, VICTORIA ALBERT

UPDATED ON: NOVEMBER 14, 2019 / 6:56 PM / CBS NEWS

A 16-year-old boy pulled a handgun out of his backpack at a Southern California high school Thursday morning and shot five of his fellow students, killing two, before he turned the gun on himself, police said. Los Angeles County Sheriff Alex Villanueva told reporters the suspect was in “grave condition” at a hospital.

The deceased victims were identified as a 16-year-old girl and a 14-year-old boy. The wounded victims were identified as a 15-year-old girl, a 14-year-old girl and another 14-year-old boy, and Villanueva said they were not in critical condition.

Sheriff’s Department Captain Kent Wegener said the gunman, who turned 16 Thursday, and the victims all attended Saugus High School in Santa Clarita. Police didn’t identify the gunman other than describing him as Asian; law enforcement sources told CBS News the suspected shooter has been identified as Nathaniel Berhow.

Police were not looking for any other suspects, Wegener said. A weapon was recovered from the scene.

“It’s a .45-caliber semiautomatic pistol, which had no more rounds in it, had no more bullets in it,” Wegener said. CBS Los Angeles reported that classes had not gotten underway when the shooting occurred, so the campus was not completely full. All Friday classes have been canceled in the district, officials said Thursday night.

Bio of suspect’s Instagram changed following shooting

Before the shooting, police said the bio of an Instagram believed to be the suspect’s read: “Saugus have fun at school tomorrow.” The bio changed after the shooting but police are unsure who made the change.

“I can confirm that that was posted on his account, and I can also confirm that it has been changed since this incident, which means there is somebody else that has access to this account, be it a hacker, or be it a friendly who has access to his password,” Wegener said.

Officials have not yet established a motive for the crime, Wegener said. Investigators have obtained a search warrant for what they believe to be the suspect’s home.

Paul Delacourt, a representative for the FBI, said it does not appear that the suspect was motivated by an ideology or group and that authorities believe he acted alone. Delacourt acknowledged, however, that the investigation is in its early stages and that information could change.

Off-duty first responders “definitely saved lives”

The first people to arrive at the scene of the shooting were three off-duty first responders, Villanueva said at the press conference.

First on the scene was a detective from the Santa Clarita Sheriff’s Station Detective Bureau who had just dropped a family member off at the school, Villanueva said. The detective was driving away when he saw students fleeing the gunshots. Two officers also entered the school “within seconds” of the shooting, followed “within a minute” by on-duty responders from the Santa Clarita Sheriff’s Station, he added.

The trio “did not hesitate” to tend to all six of the wounded students, including the suspect, Villanueva said.

“Their actions definitely saved lives,” he added.

“I actually thought I was going to die”

In the hours following the deadly shooting, students at Saugus High School spoke to CBS News’ Jonathan Vigliotti.

“We didn’t know if the shooter had a clear view of us or not, we just sprinted and we just like prayed for our lives,” one student said. “I actually thought I was going to die.”

“My teacher quickly sprang to his feet, got up, locked the door,” said senior Mason Peters. “Turned off all the lights and then we got a bunch of desks and stuff — and then reinforced the doors and then we all just like stayed hidden.”

Sophomore Micah Turner said she witnessed the shooting firsthand.

“He shot two people and I saw that happen,” Turner said. “I just saw him fire one, two, three and then I knew, I was like I needed to get out of there.”

When asked what moments would stay with her, Turner said “His face, and just seeing that one person fall.”

“It’s going to be hard to forget,” she added. “But I’m gonna have to live with that sight in my head.”

Suspect in custody after manhunt

Police didn’t identify the gunman other than describing him as Asian; law enforcement sources told CBS News the suspected shooter has been identified as Nathaniel Berhow.

The shooting sparked a manhunt, but Villanueva said the suspect was taken to a hospital along with the victims. Wegener said the suspect shot himself in the head.

Paul Delacourt, assistant director in charge of the FBI’s field office in Los Angeles, said there was no indication of any motivation or ideology for the shooting.

Lockdown lifted at area schools

All schools in the area of the shooting went on lockdown while authorities looked for the suspect, Eric Ortiz from the sheriff’s department told CBS Los Angeles.

By early afternoon, all lockdowns were lifted, Mike Kuhlman, deputy superintendent for the William S. Hart Union High School District, said in a statement.

“Our hearts go out to the families”

Kuhlman said in the statement “our hearts go out to the families of those affected by this terrible incident.”

“Words are insufficient in times such as these,” he said.

“We are currently in the process of formulating a plan to care for our school and our community — and will continue sharing updates as we learn more — including the plan for the days ahead.”