PASADENA (CBSLA.com) — Firefighters Monday battled a two-alarm electrical fire at a Pasadena apartment building.

The blaze was reported around 11 a.m. in the 600 block of South Pasadena Avenue, across from Huntington Memorial Hospital, officials said.

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The blaze, which took approximately 20 minutes to extinguish, gutted the apartment complex and badly damaged another detached unit. It caused $1.5 million worth of damage to the structure and $300,000 to the contents.

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“All these units are uninhabitable,” said Pasadena Fire Department spokeswoman Lisa Derderian.

Four families were displaced, and a 7-year-old black Labrador retriever was resuscitated after suffering from smoke inhalation.

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One person was treated at the scene.