The company distributes car audio equipment and car alarms, and an L.A. City spokeswoman said the chemicals from that equipment may have been what was fueling the fire to burn so intensely.
Smoke and flame were visible for miles and part of the 100-by-150-foot building collapsed.
The stunned owner was barely able to speak as he looked at the rubble of the business he had owned for 25 years.
The man who leased the property to him said it was a terrible loss.
"I'm in awe. I can't believe this building just went up in smoke. I mean, this guy's got a lot of merchandise in there, you know, it's his livelihood, it's his only business, it's the only thing he knows how to do," he said.
It was a business that was doing well in spite of tough economic times.
The cause of the fire has not been determined. No one has been reported to be injured.
The Associated Press contributed to this story.
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