An accessory dwelling unit or ADU in Long Beach exploded Monday morning, injuring at least one person, the Long Beach Fire Department said.
The explosion happened at around 11 a.m. in the building located in the back of a property on Gale Avenue at West 28th Street.
After a man in his late 30s was extricated from the rubble, he was taken to a trauma center in unknown condition.
The ADU is a total loss, the fire department said, as inspectors continued to investigate the cause of the explosion.
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Firefighters were able to quickly extinguish a small fire that started with the explosion.
The front building on the property sustained minor damage.
Juan Romero, who lives in Long Beach, recalled seeing the explosion as he was on his way to work.
"I was at that stop sign and I just got missed with some debris, it was bad," Romero said.
The violent eruption damaged another home on the property as well as neighboring homes – cracking through ceilings – shattering windows, and even smashing cars from the heavy debris that flew through the area at an aggressive rate. The garden walls next to the neighbor’s house appeared to be damaged as well.
The City of Long Beach left a notice for the property owners stating the detached structure was unpermitted. With that, the owners have been ordered to demolish the unpermitted structure within 48 hours or face emergency action by the city.
The cause of the explosion remains under investigation.