The young man was identified as Oscar Davila by friends. His former teacher, Greg Schive, grieved the sudden loss.
"Yea. Today has definitely been tough on the kids as well," Schive said.
The teacher said Davila was a former John W. North High School student who graduated in 2016. He studied at UC Riverside and tutored students at his alma mater twice a week.
"He was a great student, but moreover he was just a terrific guy," Schive said.
Authorities said the man responsible for the crash is 26-year-old Edgar Verduzco. He's an LAPD officer, who is suspected of driving under the influence. LAPD Chief Charlie Beck called his career short and unremarkable.
"I cannot tell you how angry and disappointed I am," Beck said.
The CHP said Verduzco was speeding around 10 p.m. Tuesday. They said he slammed into the back of the Davila's Nissan, then struck another car.
"Very high speed driving on the carpool lane, and I knew he was going to hit someone or something," witness Omar Quintanilla said.
Several people tried to get the three victims to safety, Quintanilla said, but the flames were too intense.
"It's a huge loss for us. And we talked to all my classes today about that, and now they're working through it," Schive said.
A loved one close to the family asked for privacy, but said they created a GoFundMe page to raise money for the surviving two brothers the Davila's left behind.