Santa Clarita gunman used unregistered 'ghost gun' in Saugus High School shooting, sheriff says

Kristin Lam | USA TODAY

Show Caption Hide Caption Santa Clarita school shooting victims remembered at vigil Thousands held a vigil for Gracie Anne Muehlberger, 15, and Dominic Blackwell, 14, who were shot and killed by a classmate at Saugus High School.

An unregistered "kit gun" was used in the deadly shooting at a Southern California high school last week, authorities said Thursday.

It is unknown who bought the pistol's parts or put it together, Los Angeles County Sheriff’s Lt. Brandon Dean said in a statement. Police say Nathaniel Tennosuke Berhow, 16, fatally shot two classmates at Saugus High School in Santa Clarita and injured three others before shooting himself with the 45-caliber semiautomatic handgun.

The gun does not have a serial number to track, Los Angeles County Sheriff Alex Villanueva told KABC-TV and other local outlets. Kit or "ghost guns" can be bought online or at gun shows, Villanueva said, and people can watch YouTube videos to learn how to assemble them.

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Authorities found several other unregistered guns in Berhow's home in Santa Clarita, near Los Angeles. They are investigating where the guns came from, and noted registered guns belonging to Berhow's father were seized in 2016.

A motive has not been determined, Villanueva said. Investigators have interviewed 45 people and are working with federal authorities to get access to the suspect's cell phone, he said.

There has been no indication Berhow was affiliated with a group or ideology, said Paul Delacourt, the agent in charge of the FBI’s Los Angeles field office.

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Previously, Villanueva said the 16-second shooting blitz was deliberate and Berhow seemed familiar with the weapon. The gun jammed at one point, but he quickly cleared it.

A vigil for the victims was held on Sunday. No relationship between the shooter and the victims has been identified, authorities have said, other than that they attended the same school.

No classes have been held at the high school since the Nov. 14 shooting. Students will return after Thanksgiving break, on Dec. 2, according to the school's website.

Contributing: Mike James, USA TODAY; The Associated Press