A suspected arsonist is accused of sparking a Bay Area home hearth that killed his father, 2-year-old niece and 5-year-old nephew — as the victims’ heartbroken household spoke out about the surprising tragedy.

Sergio Rivera-Vega, 32, was arrested for allegedly lighting the blaze Tuesday night time at the residence in the 200 block of fifteenth Street in Richmond, where he lived with other kin.

Sergio Rivera-Vega, 32, was arrested for allegedly lighting the blaze Tuesday night time. KRON4

When firefighters arrived, they discovered 4 victims inside the residence, including Rivera-Vega’s 47-year-old father, Jose Rivera, who was pronounced useless at the scene.

Three others — including Rivera-Vega’s 2-year-old niece, Joline, and 5-year-old nephew, Andrew — later died of their accidents. 

The youngsters’s mom stays in the hospital in crucial situation “fighting for her life,” a member of the family wrote in a GoFundMe web page.

The suspect’s 2-year-old niece, Joline, and 5-year-old nephew, Andrew, died after the hearth. Gofundme

The suspect’s 47-year-old father, Jose Rivera, was pronounced useless at the scene. Gofundme

“My mom and I are heartbroken and overwhelmed trying to process so much loss all at once,” the fundraiser learn.

“We urgently need help with funeral services and burial expenses for my dad, my niece, and my nephew.”

The relative said she’s at the moment unemployed, and the tragedy has left them struggling to cowl the “costs while supporting my mom and praying for my older sister as she continues to fight for her life in the hospital.”

On Thursday night time, family members gathered outside the residence for a small personal memorial. Gofundme

“Anything will help, no matter how small. Please support us during this heartbreaking time. If you are not able to donate, please keep my family in your prayers and share this fundraiser. Thank you from the bottom of my heart for any love and support,” it added.

On Thursday night time, family members gathered outside the residence for a small personal memorial, ABC7 News reported.

Police said Rivera-Vega, who lived at the residence, was arrested close to the scene. He was booked on two counts of homicide and two counts of arson inflicting nice bodily damage. His bail has been set at $2.5 million.

2-year-old Joline died after the hearth. Gofundme

“We extend our deepest condolences to the family and loved ones affected by this senseless and tragic event,” a message from the police division learn.

“Our thoughts are also with the woman and young child who remain hospitalized as they continue to fight for their lives.”

Police said the investigation is ongoing.