Lars Sanchez, 4

[Update: Authorities identified the woman who killed Lars Sanchez before taking her own life as his mother, Yolanda Tijerina, 43. Tijerina had come to the attention of Los Angeles County social workers nine months earlier when the principal at her son's preschool called the child abuse hotline to report her erratic behavior.

Read more Times' coverage about this case: Boy's death shows weaknesses of L.A. County's child welfare system]

Lars Sanchez, a 4-year-old Latino boy, was stabbed to death July 18 in the 300 block of Vista Place in Highland Park, officials said.

Sanchez was apparently killed by a woman, who was also found dead in the home with her wrists slit, authorities said.

The woman, who has not been identified, and child were pronounced dead at the scene, a home on a narrow alley across the street from Garvanza Park, said Los Angeles Police Department Officer Rosario Herrera.

“It’s a brutal scene in there,” Murphy said.

Murphy would not say whether the victims had been involved with the county’s department of children and family services. He said county staff were not at the scene.

Neighbor Henry Lemus, 26, a restaurant server’s assistant, said he was shocked when he heard the news. Although he did not know them well, he was aware that a small child lived in the house. 

“It’s sad because sometimes we hear that little kid crying,” Lemus said.

Lemus, a father of three, said that if he had realized the victims were in troubled, he would have intervened. “I wish I could have done something about it,” Lemus said. “I would have gone in and taken that kid away. But it’s too late now.”

Lemus and several other neighbors said they believe that an older woman also lived in the house, possibly with two grown daughters. He and other neighbors did not know the names of the people living there.

Neighbors stood in their driveways as police cordoned off surrounding streets and strung up yellow crime-scene tape.

Carlos Mendoza, 39, a bellman at a Hollywood hotel, said he moved to the neighborhood with his wife two years ago because he considered it safe.

“It was kind of strange to see something like this,” he said as he walked his dog past several police cars.

Alfred Glen, 46, a father of two, said he has lived in the neighborhood 25 years and was not worried about his family’s safety until today.

“It’s tragic,” he said of the deaths. “I try to shield my family from the news, but then it hits home.”

-- Ari Bloomekatz

Photo: A Highland Park neighbor of Yolanda Tijerina reacts upon hearing the news of the deaths of Tijerina and her son, Lars Sanchez. Lars had been decapitated and Tijerina had a knife wound to her wrist. Credit: Christina House/For The Times