Authorities Thursday said the preliminary cause of a fire in a Pasadena apartment that left a 4-year-old boy dead and his mother and 3-year-old brother critically injured was an electrical problem involving the refrigerator.

Firefighters were dispatched at 2 p.m. Wednesday to 169 E. Washington Blvd., near North Summit Avenue, according to Pasadena’s public information officer, Lisa Derderian.

Crews arrived within three minutes, but a lower-level apartment unit was already well-involved, and flames were spreading to upper units. Fifty-five firefighters extinguished the second-alarm fire at 2:30 p.m., Derderian said.

The 4-year-old was pronounced dead at the scene, Derderian said. His younger brother and their 29-year-old mother were taken to a hospital in critical condition, Derderian said.

The fatally injured boy was identified by family members as Kevin Arias, according to Fox11, which reported that his mother, Nancy, and his brother, Jordan, were hospitalized.

The preliminary cause of the fire was an electrical problem involving the refrigerator, Derderian said. A dog also died in the fire, Derderian said.

The American Red Cross assisted about a dozen people displaced from the building. A chaplain program newly implemented by the fire department provided counseling for firefighters at the scene, some of whom have young children of their own, Derderian said.

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