What's being investigated as an arson fire killed a 37-year-old father and his one-year-old daughter inside their Oakland home early Saturday morning; police have deemed the incident a double homicide.

As reported by ABC7, Oakland Police Chief LeRonne Armstrong was called to a "horrific scene" around 3 a.m. after investigators realized a fire that started at 12:15 a.m. on Stearns Avenue didn't appear to be accidental. It became increasingly clear the swift-moving blaze — which was responsible for the death of a thirtysomething father and his young daughter — wasn't started by accident.

Somebody (or somebodies) had the intention of maiming or killing the residents inside the domicile.

"Just an all-around, really horrific scene," says Armstrong. "One in which you wouldn't expect to see in Oakland. One in which you wouldn't expect someone to be so callous."

The fire started across from Bishop O'Dowd High School, where neighbors were seen gathering outside as the otherwise sleepy part of Oakland's Grass Valley neighborhood, sitting right outside of the Oakland Zoo, began glowing orange from a deadly inferno.

Mohammed Al Samma, a security guard who also lived in the home, received a call that his house was on fire — prompting Al Samma to immediately leave work early and rush home. Returning back to the house, Samma was informed his cousin and cousin's daughter had died. His cousin's pregnant wife managed to make it out of the home alive, though she was later transported to a local hospital to have burns treated; her husband died apparently going back into the home to save the pair's one-year-old, who would've celebrated her second birthday next month.

(Al Samma said to the news outlet that some of his family members were awake when it happened, noting that a group of people threw Molotov cocktails at the home.)

Police are describing the fire as "suspicious," now working with the Oakland Fire Department's Arson Investigation team, as well as the Alameda County Arson Task Force and Alcohol, Tobacco and Firearms (ATF), to determine possible suspects.

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