BBC: Two students, aged 16 and 14, have been killed and three others injured by a gunman who opened fire at a secondary school in California, officials say.
The victims died in a brief, 16-second gun attack shortly before classes began on Thursday at Saugus High School in Santa Clarita, north of Los Angeles.
The attack came on the 16th birthday of the suspect, named by US media as fellow student, Nathaniel Berhow.
The suspect then shot himself in the head and is in a critical condition.
Students and teachers spoke of how they barricaded themselves in classrooms amid chaotic scenes, carrying out an active shooter drill that many schools have implemented in recent years following deadly attacks around the country.
What do we know about the shooting?
It was first reported at 07:38 local time (15:38 GMT) on Thursday, LA county sheriff Alex Villanueva said, adding that police were at the scene within two minutes.
The suspect was standing in the school courtyard when he took a .45-calibre semi-automatic pistol from his backpack and opened fire for about 16 seconds before turning the gun on himself, Sheriff’s Captain Kent Wegener said.
“He just fires from where he is. He doesn’t chase anybody. He doesn’t move,” Capt Wegener said.
Students barricaded themselves in classrooms under an active shooter drill for more than an hour as police tried to determine if the gunman was still at large.
Officers found six people suffering from gunshot wounds and transferred them to local hospitals. The suspect was later identified as one of those injured.
What do we know of the victims?
The names of those who died and have not yet been released. They were a 16-year-old girl and a 14-year-old boy.
The three injured, also as-yet unnamed, were two girls, aged 14 and 15, and a 14-year-old boy. They are all in a stable condition.
All attended Saugus High School.
The suspect had no known connection to the victims, Capt Wegener said.
What has been revealed about the gunman?
The attack came on the suspect’s 16th birthday. The motive for the attack is unknown.
The FBI said it appeared he had acted alone and was not affiliated with any particular group or ideology.
The Associated Press quoted a fellow student, Brooke Risley, as saying the suspect was introverted but “naturally smart”, adding that he had a girlfriend and was a boy scout.
AP said the boy lived locally in a modest home, and that his father died two years ago. A neighbour told Reuters the boy had struggled with his father’s death.
Investigators have searched the home and interviewed the boy’s mother and girlfriend.
There were no initial indications that he had been bullied at school.
There were reports of an Instagram posting saying “Saugus have fun at school tomorrow”, but it was later revealed the account was not owned by the suspect.