Los Angeles County Sheriff Alex Villanueva Thursday said the gun used in the shooting attack at Saugus High School that killed two students and wounded three others — before the 16-year-old shooter turned the gun on him and later died — was an untraceable “kit gun,” known as a “ghost gun.”

“The report on the firearm indicates that the handgun used in the assault was not manufactured conventionally and may be some form of a `kit gun’ assembled by a consumer rather than a manufacturer, from pieces bought separately,” according to a statement from the Los Angeles County Sheriff’s Department.

“We have no evidence to indicate who assembled it or bought the components,” according to the statement.

Los Angeles County Sheriff Alex Villanueva told ABC7 that school shooter Nathan Berhow’s father had six registered guns that were lawfully removed from the home and subsequently destroyed. A later search of the Berhhow home turned up a “kit gun.”

“The weapon used in the homicide was a kit gun,” Villanueva said. “It was assembled from parts. It had no serial number. So it become as what is known as a `ghost gun.”’

The sheriff said kit guns are sold at gun shows and can be bought online and are also known as “80-percent guns.”

“So you can 80 percent is assembled already and you get the additional 20 percent — and they’re sold as a kit,” he said. “You can legally buy it, assemble the weapon yourself.”

The Los Angeles Times reported that investigators are examining Berhow’s electronic communications in an effort to find a discover a motive for the shooting.

“We’re working with some federal entities to help us unlock the cellphone to get to that information. So that’s one of the challenges,” Villanueva told ABC7.

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