The sheriff's office identified the victims as 35-year-old Gladis Plumlee, her 15-year-old son and her 14-year-old daughter. Family members and friends gathered near the home later Wednesday, leaning on one another as they grieved.
Porterville Fire Chief Bryan Cogburn said the fire started around 12:30 a.m. near Plano and Harrison.
"It's hard to put into words how heartbreaking this is," Cogburn said. "Porterville is a tight-knit community. This hits home for everybody, including my own firefighters."
When crews arrived, they found a two-story home heavily involved in flames.
"Upon arrival, crews encountered a two-story home with heavy fire involvement," Cogburn said.
Cogburn said firefighters launched an aggressive attack and search.
"Our crews then initiate an aggressive fire attack and search, locating the three victims. Unfortunately, they were deceased," he said.
Two people escaped the fire, according to Cogburn.
"The father and the oldest daughter survived," he said.
Nearly 12 hours after the fire, crews were still investigating the scene as family and friends gathered across the street from the charred home.
Pink "14" balloons remained hanging in the backyard.
"I don't have all the information on the balloons... we do know that one of the victims was 14 years old," Cogburn said.
The Porterville Unified School District released a statement saying it "extends our deepest condolences to the family impacted by this tragic fire. We have deployed counseling and support teams to Porterville Military Academy and Granite Hills High School to assist any students and staff who may be affected."
The cause of the fire remains under investigation.
There is a nearby elementary school that remained open today, but students remained indoors on Wednesday.
Crews will be on scene throughout the day and night to monitor any hot spots.
Family members have created a GoFundMe page for anyone looking to help with funeral arrangements.
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