The third fatal shooting occurred in the 12900 block of Filmore Street, where a woman was shot in her car. Residents called police after hearing the gunfire. Family and friends identified the victim as Gloria Esperanza Tobar, 59.
The identities of the other victims were not released as authorities worked to notify next of kin.
The owner of the house, who did not want to be identified, said the family that had been shot had lived next door to him until a few years ago.
"They were a beautiful Catholic family, all the time in church," he said.
At the church, officials deferred to an archdiocese spokeswoman, who would not identify the family but said those who knew them were grieving.
"I can tell you it's a very difficult time for the parish community. They were very active and well-loved in the church," said the spokeswoman, Monica Valencia.