Ambulances are parked outside of Saugus High School after reports of a shooting on Thursday, Nov. 14, 2019 in Santa Clarita, Calif.

Two students — a 16-year-old girl and 14-year-old boy — were killed and others injured in a shooting at a Santa Clarita, California high school on Thursday, Los Angeles County authorities said.

The suspected gunman was identified as Nathaniel Tennosuke Berhow, 16, multiple law enforcement sources told NBC News. Authorities said Berhow's 16th birthday was on Thursday. No motivation or ideology has been determined yet.

Berhow is in custody and in "grave condition" at the hospital, Los Angeles County Sheriff Alex Villanueva said at a press conference. Multiple officials initially said Berhow was dead.

Police and firefighters responded to reports of a shooting at 7:38 a.m. PT and arrived on the scene shortly after, authorities said during a press conference. When first responders arrived at the high school, they found six students with gunshot wounds, including the suspected shooter.

The suspect, later identified as Berhow, pulled out a gun in the high school quad and shot five students and then himself, authorities said during the press conference. A .45-caliber semi-automatic pistol was recovered at the scene and did not have any more bullets in it.

Authorities identified the other victims as two females, one aged 14 and the other aged 15, and one male who is 14 years old.

Initial reports from the Los Angeles County Fire Department indicated there were as many as seven victims, but authorities revised that number as information became more clear.

The high school, which is almost 40 miles north of Los Angeles, counts roughly 2,400 students, according to its website.