Video Shows Man Pull Out Knife Moments Before Fatally Stabbing High School Student, 17: LAPD

The Woodrow Wilson High School student was attacked last Friday as he waited for his mother to pick him up outside King Torta restaurant in El Sereno, California.

On Tuesday, detectives from the Los Angeles Police Department's homicide unit released surveillance footage of the moments leading up to the attack, as they asked for the public's help identifying a suspect.

The video shows a man with long black hair wearing a leather jacket walking through a parking lot after exiting his vehicle, before approaching the teenager on the sidewalk while appearing to pull out a large knife.

According to police, the man then stabbed Chavarin multiple times in the back; The suspect then fled the scene, before the teenager died inside the restaurant.

Police believe the same suspect attacked a 33-year-old man five hours later, around 8:55pm. The suspect stabbed the victim several times without saying anything and appeared to be wearing the same clothing as the man involved in the earlier attack, authorities say. The second victim survived.

"It breaks my heart, the fact that they just took him away from me," Xavier's mother Laura Frias told NBC4. "I don't know what to say. [I am] just so heartbroken. He was my love, my everything."

Chavarin is remembered by family members, friends and his school as a "great big brother" and straight-A student who was going to graduate with honors.

On Wednesday morning, police surrounded a home in Alhambra, before a standoff with the man they believe is responsible for the attacks. The man, who was later identified as 33-year-old David Zepeda, eventually emerged from the home and surrendered.

"I don't want to taint the investigation, [but] he is not going to be able hurt anyone else,” Commander German Hurtado of the LAPD told the LA Times after the surrender.

Before he was apprehended, Hurtado told KTLA the suspect had prior mental health incidents.