LOS ANGELES (AP) — Los Angeles County sheriff’s investigators suspect illegal fireworks sparked a fire that caused minor injuries to four firefighters and caused up to $3 million in damage to three warehouses.

They said witnesses reported seeing a group of young men shoot fireworks at mattresses outside one of the warehouses in an industrial area of South Los Angeles. The fire spread to the inside and several nearby buildings.

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Fireworks debris was found at the scene, authorities said.

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“They said it’s a total loss,” Daniela Avila, who works at a furniture company owned by her boyfriend.

“This is our second home, if anything our first home. We spent more time here than at our own home so this is hard,” Avila said.

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