Police investigating a high school shooting in California said on Friday they still did not know what motivated the suspect, who killed two classmates and wounded three others before shooting himself in the head and collapsing.
Thursday morning's shooting at Saugus High School in Santa Clarita, about 65 km north of Los Angeles, took place in a matter of just seconds. The suspect pulled a .45 semi-automatic pistol from his backpack in an outdoor school courtyard and opened fire.
Sheriff Alex Villanueva of the Los Angeles County Sheriff's Office said on Friday that why was the question of the day.
"This kind of came out of the blue," the sheriff told CNN. "It shocked everyone who knew him."
Police have not released the name of the suspect, but have said it was his 16th birthday on Thursday. Authorities said he was in grave condition at a hospital.
"He saved the last round for himself," Villanueva said.
Investigators are looking into the suspect's past and social media accounts and interviewing people who knew him, the sheriff added.
"We're still digging," he said.
The FBI is assisting in the investigation and police do not know yet where the suspect got the weapon, the sheriff said.
Two girls aged 14 and 15 were being treated at Providence Holy Cross Medical Center in Mission Hills, California and were listed in good and fair condition, a hospital spokeswoman said early on Friday.
At the Henry Mayo Hospital in Santa Clarita, authorities said a 14-year-old boy was treated and released, and the other students taken there died.
No names of the wounded or the dead were released yet, but the two slain students were a 16-year-old girl and a 14-year-old boy.
Captain Kent Wegener of the Los Angeles County Sheriff's Department said surveillance video footage showed the suspect opening fire from a single stationary position and shooting his victims in rapid succession before turning the gun on himself.
The scene at Saugus High School was reminiscent of other mass shootings at US schools, including Marjory Stoneman Douglas High School in Parkland, Florida, where a former student with an assault gun killed 17 people on Feb. 14, 2018.
It was the 85th incident of gunfire at a school this year, according to Everytown, a gun control advocacy group. Police said the suspect had acted alone. Investigators descended on his family home, blocking off the street. They found no further danger there.