According to Los Angeles Police Department investigators, Rosa Figueroa and her daughter, whose name was withheld, had been targeted by the suspect, 25-year-old Juan Carlos Cardenas, for some time. Figueroa had a restraining order against him.
Around 4 p.m., investigators said the women were trying to persuade Cardenas to drive to a hospital to get help for a drug addiction problem. Cardenas drove the women to the 13300 block of Borden Avenue in Sylmar. A witness said they saw the women get out of the SUV, Cardenas chase them down and assault them.
"He got out of the SUV with a pipe and went after the older woman," LAPD Lt. Paul Vernon said. "Our witness actually saw him strike her multiple times in the head and she died here at the scene."
Cardena's ex-girlfriend survived the attack thanks in part to a 40-year-old good Samaritan who happened to be in the area at the time. She sustained fractures to her face, but was expected to survive.
"This man, through a methamphetamine addiction apparently, has been terrorizing both these families, his ex-girlfriend's family that he shares a 2-month-old child with, as well as his own family," Vernon said. "When his own family arrived here they talked about the fact that he had been arrested a month or so ago, spent 12 days in jail for choking his own mother."
Investigators said they recovered the pipe used in the attack.
Cardenas was booked on suspicion of murder and attempted murder.
City News Service contributed to this report.