Authorities Confirm New Details From Santa Monica Shooter's Past

SANTA MONICA (CBSLA.com) — Authorities have confirmed new details about the violent past of John Zawahri, the man accused of killing five people and injuring five others during a shooting rampage in Santa Monica.

Zawahri is accused of killing his father, 55-year-old Samir, and his 25-year-old brother, Christopher, at their Yorkshire Avenue home before going on a shooting spree on city streets and at Santa Monica College, where he was enrolled as a student as recently as 2010.

He was eventually gunned down by police in the school's library.

Several sources confirm that Zawahri was placed on a 72-hour-mental health hold in 2006 after he was found searching for assault weapons on the internet while in class. He also allegedly threatened to do harm to students.

COMPLETE COVERAGE: Santa Monica Rampage

At the time, Zawahri was a 16-year-old student at Olympic High School, a continuation alternative school in Santa Monica.

Sandra Lyon, School Superintendent for the Santa Monica-Malibu School District, told KCAL9's Dave Lopez that school authorities responded immediately to the 2006 incident.

"I can't talk about his specifics, but I can tell you that when we did have a teacher who was concerned about his discussion around violence and weapons that we immediately did our process and contacted the local authorities," said Lyon.

"I can say confidently that we did everything that we should have done in this instance," she said.

Though they declined to appear on camera, Santa Monica Police confirmed that officers took Zawahri to the UCLA psychiatric ward. The teenager was then released, reportedly against their wishes.

Police also confirmed Tuesday that Zawahri used an AR-15 semiautomatic rifle in the shootings, in addition to a handgun.

They said there is a strong possibility that both weapons may have been legally registered to Zawahri's father, Samir.

Authorities also reportedly have a good lead on where Zawahri might have purchased the ammunition.

A woman at the apartment of Randa Abdou, the suspected gunman's mother, said Abdou is in hiding.

Multiple reports have suggested that Zawahri's mental health problems may have stemmed from his parents' messy divorce and domestic abuse in his home.

On Monday, Abdou issued a statement through a neighbor in which she said she was "in mourning" and expressed sadness for the victims.