Explosion at Southern California medical office forces nearby daycare to evacuate

An explosion rocked a Southern California medical office building Tuesday, killing one person and injuring three others, authorities said.

Orange County Fire Authority Chief Brian Fennessy said 70 firefighters were dispatched in response to a 1:09 p.m. Tuesday call from Aliso Viejo.

The blast involved a building under renovation but the cause was not immediately known, Fennessy said.

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The explosion blew siding off the walls, exposing insulation and framing. Federal, state and local investigators were on the scene.

“The corner of that building, the whole bottom floor is pretty much blown out,” fire Capt. Tony Bommarito said.

There was no immediate information about the person who was killed. The injured were taken to a hospital.

Mary McWilliams told the Orange County Register that she arrived for an appointment to find smoke surrounding the area and car alarms going off.

McWilliams said she saw two burned women staggering out of the building, covered in ash and soot.

One woman, who had skin peeling on her arm from burns, said, “Take care of my mother,” McWilliams said. The other woman was bleeding from her head.

“I thought it was a little fire until I saw everyone’s faces and reactions,” McWilliams said.

Fennessy said children at a daycare across the street were not injured.

Little children holding hands and others being pushed in rolling cribs were led by firefighters to a Target parking lot to be united with parents.