They said that the woman was one of the original employees of the La Mirada restaurant and that her husband worked at an In-N-Out in Orange County.
Just before 5 a.m., sheriff's deputies responded to a call of an unresponsive woman near the In-N-Out restaurant in the 14300 block of Firestone Boulevard, said Deputy Guillermina Saldana, spokeswoman of the Los Angeles County Sheriff’s Department.
Deputies found the woman dead from a gunshot wound to the upper torso. She was wearing her In-N-Out Burger uniform.
Investigators have few leads in the case.
Detectives hope that by publicizing details of where the victim worked, someone might come forward with information.
In-N-Out owner and President Lynsi Snyder identified the employee as Josefina Alcocer, who had been working with the company for about 20 years. Snyder expressed sadness over her death.
"The entire In-N-Out family grieves today over this senseless tragedy as we send our thoughts and prayers to the Alcocer family," Snyder said in a statement. "Josefina had been a part of our In-N-Out family since 1996, and she was one of our original associates at our La Mirada restaurant.
"We are devastated and will miss her. So many things going on in the world today. We will remain strong and stand in love for Josefina. God bless and comfort all who are mourning a loved one at this time."
"I just can't get over it," Alma Uribe, a friend, told KNBC. "It's kind of hard because she was like my daughter. I can't even imagine who would do something like that to her because she was a very giving person."
Officials said cellphone videos could help identify the attacker.
"That's the advantage we have nowadays. We rely on cameras all the time. That's going to be part of our investigation. We just haven't gotten that far yet," Lt. Steve Jauch of the sheriff's Homicide Bureau told KTLA News. "We're going to be looking at that."
The woman is the first person to be killed in La Mirada in the past 12 months, according to the Los Angeles Times Homicide Report.
La Mirada is about 17 miles southeast of downtown L.A.
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