Berhow, who turned 16 Thursday, died at 3:30 p.m. Friday of a self-inflicted wound, the television station reported.
Berhow did not appear to be linked to a terrorist group and had shown no previous signs of violence, authorities said at a news conference. Capt. Kent Wegener of the Los Angeles County Sheriff's Department said more than 40 interviews had been conducted and Berhow's home was searched, The Associated Press reported.
“We did not find any manifesto, any diary that spelled it out, any suicide note or any writings,” Wegener said.
Los Angeles County Sheriff Alex Villanueva told The Washington Post that the gunman appeared to be taking random shots at Saugus High School but appeared "very familiar with firing the weapon" and did not commit a "spur-of-the-moment act."
Update 7:50 p.m. EST Nov. 15: Police say 16-year-old boy who shot five students at his Los Angeles-area high school has died.
People who knew the boy described him as a quiet, smart kid who they’d never expect to turn violent.
Update 7:30 p.m. EST Nov. 15: Authorities have identified the second student killed in a shooting by a fellow student at a Southern California high school.
The Los Angeles County coroner’s office says 14-year-old Dominic Blackwell died Thursday along with 15-year-old Gracie Muehlberger.
Two teenage girls remain hospitalized but are expected to be released over the weekend. A third student was treated and released.
Update 3:20 p.m. EST Nov. 15: Los Angeles County coroner's officials on Friday identified one of the two teenagers slain Thursday after a student opened fire on classmates at Saugus High School as Gracie Anne Muehlberger, 15, according to The Los Angeles Times.
The newspaper reported she celebrated her 15th birthday on Oct. 10.
A 14-year-old boy killed in the shooting was not immediately identified, according to KCBS-TV.
Update 6:37 a.m. EST Nov. 15: The suspect has been identified by two separate law enforcement sources as Nathaniel Berhow, CNN and the Los Angeles Times reported.
The Los Angeles County Sheriff's Department has not confirmed his identity due to his age, CNN reported.
Neighbors described Berhow as a good student and typical teenager who was affected by the death of his father in 2017, CNN reported.
Neighbors said Berhow found his father dead after had a heart attack, KTTV reported.
His mother and father had divorced in 2016, CNN reported.
There is no motive for the attack, according to Los Angeles County Sheriff's Office.
Members of the community gathered near the campus Thursday night to remember the victims, KNBC reported.
The Associated Press reported the gunman shot whoever was near him and that there was no known connection to the victims.
Update 3:10 p.m. EST Nov. 14: Los Angeles County Sheriff's Department Capt. Kent Wegener identified the gunman as a 16-year-old student who opened fire on his classmates on his birthday.
Wegener said video from the scene showed the teenager, who was not identified by name, taking a gun out of his backpack in the quad at Saugus High School on Thursday morning. He shot five of his classmates before turning the gun on himself.
Sheriff Alex Villanueva told reporters Thursday that the suspect shot himself in the head. He was among six people transported to the hospital after the shooting.
Two students died in Thursday's shooting, a girl and a boy. Authorities did not identify the victims by name.
Update 2:30 p.m. EST Nov. 14: Authorities in Los Angeles County are holding a news conference Thursday to update the public on Thursday morning's deadly shooting at Saugus High School.
Update 1:05 p.m EST Nov. 14: Officials with Henry Mayo Hospital confirmed a female died after being taken to the hospital following a shooting at Saugus High School.
It was not immediately clear whether the victim was a student. Hospital officials said three other male victims were taken to the hospital with injuries after shooting. Two of the victims were listed in critical condition while the third was listed in good condition.
Update 12:50 p.m. EST Nov. 14: Los Angeles County Sheriff Alex Villanueva said a suspect was in custody after Thursday morning's shooting at Saugus High School.
Authorities were expected to provide more details at a news conference scheduled Thursday morning.
Update 12:35 p.m. EST Nov. 14: Officials at Henry Mayo Hospital confirmed they had received four patients after a gunman opened fire Thursday at Saugus High School.
Hospital officials said the victims included three males and one female. All the victims, aside from one male in good condition, were listed in critical condition in the immediate aftermath of the shooting.
Update 12:30 p.m. EST Nov. 14: Parent Brian Skiba told KCBS-TV that his daughter ran into a classroom when she heard shots fired Thursday morning at Saugus High School.
"She heard the shots ... she in the quad, where it started, and ran into the band room," Skiba told the news station. "(She) locked the door behind her and told everybody to get down."
Skiba told KCBS-TV a police officer was in the band room with about 50 students Thursday.
"I'm still pretty shook up," Skiba said.
Update 12:10 p.m. EST Nov. 14: Sheriff's deputies told KNBC-TV that they were surrounding two locations Thursday morning in Santa Clarita, including a home believed to be the suspect's residence.
KTLA reported authorities believe the gunman was a student at Saugus High School.
Officials asked residents in the area to stay inside and keep their doors locked as they continued to investigate Thursday.
Update 12 p.m. EST Nov. 14: White House Deputy Press Secretary Judd Deere said President Donald Trump was monitoring reports of Thursday morning's shooting in Santa Clarita.
"The White House encourages all those in the area to follow the advice of local law enforcement and first responders," Deere said.
Update 11:50 a.m. EST Nov. 14: Officials with Henry Mayo Hospital in Valencia said two people were taken to the hospital in critical condition after Thursday morning's shooting at Saugus High School.
Hospital officials said three other victims were en route to the hospital Thursday morning. Their conditions were not immediately known.
Update 11:45 a.m. EST Nov. 14: Deputies asked residents in the area of Saugus High School to lock their doors and shelter in place as they continue to search for a shooter who opened fire Thursday morning at the school.
Update 11:30 a.m. EST Nov. 14: Authorities revised down the number of people injured in Thursday morning's shooting from seven to three, according to KNBC-TV.
Sheriff's deputies warned the incident was active and ongoing Thursday morning.
Original report: Deputies said nearby schools were placed under lockdown as authorities investigated.
Officials with the Los Angeles County Fire Department told KNBC that at least seven people were shot. Their conditions were not immediately known.
Check back for updates to this developing story.