A teen wielding a semiautomatic handgun opened fire at a Southern California school on Thursday morning, killing two of his fellow students and injuring several others before fatally wounding himself.

Police said they responded to a report at 7:38 a.m. local time of an active shooter situation at Saugus High School in Santa Clarita. Officers arrived on the scene two minutes later and found several people shot, Capt. Kent Wegener of the Los Angeles County Sheriffs Homicide Bureau said at a news conference.

Three other teenagers, including a 14-year-old girl, a 15-year-old girl and a 14-year-old boy, were hospitalized after the shooting. Two of the teens were released in good and stable condition. Only one student remained in critical condition and was still receiving treatment as of late Thursday afternoon, hospital officials said.

The 16-year-old suspect, identified as Nathaniel Tennosuke Berhow, was hospitalized after shooting himself in the head. He died at the hospital at 3:30 p.m. Friday.

School security footage showed Berhow arriving on campus Thursday morning, removing a .45-caliber handgun from his backpack and shooting at five students in the quad. Berhow then shot himself in the head. The attack lasted 16 seconds.

Investigators believe that Berhow appeared to have planned the shooting but shot students at random.

It wasnt a spur-of-the-moment act, Los Angeles County Sheriff Alex Villanueva said at a news conference Friday.

A motive for the shooting has not been determined. Police said it was the suspects birthday.