Deputies and firefighters responded just after 7:30 a.m. to a report of a fire in the 17900 block of Santa Ana Drive, the San Bernardino County Sheriff's Department said Thursday in a statement.
The agency identified the victims as Beatrice Gonzalez, 6; Priscilla Gonzalez, 8; and Karina Gonzalez, 35. The woman, who was found unresponsive in front of the residence, died shortly after being rushed to a hospital.
The bodies of the children and the suspect, Eric Gonzalez, were found in a bedroom as firefighters extinguished the blaze, according to a news release.
Handguns were recovered inside the residence, the statement said. Arson investigators determined the fire was intentionally set.
Anyone with information about the incident is asked to call the sheriff's homicide Detective Nick Clark at (909) 387-3589.