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Orange County sheriff's officials say Rivera was shot and killed by his own friend in front of his home in Lake Forest Thursday night. He was taken to a hospital where he later died.
Click in the Eyewitness News story window above to watch Subha Ravindhran's report from the scene, including an interview with one of the victim's friends.
Early Friday morning Orange County authorities arrested the suspected gunman.
"At 5:30 this morning, we did follow up to an address in Santa Ana where we did arrest who we believe is the shooter a 19-year-old man,""said Jim Amormino of the Orange County Sheriff's Department. "A few hours later we did arrest another occupant of the vehicle, and I'm not ruling out additional arrests."
Deputies say gunfire rang out in front of Rivera's home on the 25000 block of Ankerton Drive near Larkwood Lane around 8 p.m. Thursday. They say shootings like this are rare in Lake Forest. The community is known to be the 10th safest city in the United States.
"I never hear anything around here," said neighbor Aldina Campos. "I go around sometimes late, like 6:30, all around here, in the park, and it's very safe."
Authorities say Rivera lived in the home with his parents and had an 18-month-old son.
Friends say Rivera, who they called Alex, loved working on cars and going off-roading. They say he will be missed.
"It just shows that life is precious, you got to take everything in as it goes," said Jesse Slios, a friend of Rivera. "It sucks that it happened to such a good guy. It always happens that way, the good die young. I mean he's, he was a real good guy."
Authorities are looking for other possible accomplices. If you have any information please call the Orange County Sheriff's Department at (949) 770-6011.